1 //===--- Driver.cpp - Clang GCC Compatible Driver -------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "clang/Driver/Driver.h"
11 #include "InputInfo.h"
12 #include "ToolChains.h"
13 #include "clang/Basic/Version.h"
14 #include "clang/Config/config.h"
15 #include "clang/Driver/Action.h"
16 #include "clang/Driver/Compilation.h"
17 #include "clang/Driver/DriverDiagnostic.h"
18 #include "clang/Driver/Job.h"
19 #include "clang/Driver/Options.h"
20 #include "clang/Driver/SanitizerArgs.h"
21 #include "clang/Driver/Tool.h"
22 #include "clang/Driver/ToolChain.h"
23 #include "llvm/ADT/ArrayRef.h"
24 #include "llvm/ADT/STLExtras.h"
25 #include "llvm/ADT/StringExtras.h"
26 #include "llvm/ADT/StringSet.h"
27 #include "llvm/ADT/StringSwitch.h"
28 #include "llvm/Option/Arg.h"
29 #include "llvm/Option/ArgList.h"
30 #include "llvm/Option/OptSpecifier.h"
31 #include "llvm/Option/OptTable.h"
32 #include "llvm/Option/Option.h"
33 #include "llvm/Support/Debug.h"
34 #include "llvm/Support/ErrorHandling.h"
35 #include "llvm/Support/FileSystem.h"
36 #include "llvm/Support/Path.h"
37 #include "llvm/Support/PrettyStackTrace.h"
38 #include "llvm/Support/Process.h"
39 #include "llvm/Support/Program.h"
40 #include "llvm/Support/raw_ostream.h"
41 #include <map>
42 #include <memory>
43 
44 using namespace clang::driver;
45 using namespace clang;
46 using namespace llvm::opt;
47 
48 Driver::Driver(StringRef ClangExecutable, StringRef DefaultTargetTriple,
49                DiagnosticsEngine &Diags)
50     : Opts(createDriverOptTable()), Diags(Diags), Mode(GCCMode),
51       SaveTemps(SaveTempsNone), ClangExecutable(ClangExecutable),
52       SysRoot(DEFAULT_SYSROOT), UseStdLib(true),
53       DefaultTargetTriple(DefaultTargetTriple),
54       DriverTitle("clang LLVM compiler"), CCPrintOptionsFilename(nullptr),
55       CCPrintHeadersFilename(nullptr), CCLogDiagnosticsFilename(nullptr),
56       CCCPrintBindings(false), CCPrintHeaders(false), CCLogDiagnostics(false),
57       CCGenDiagnostics(false), CCCGenericGCCName(""), CheckInputsExist(true),
58       CCCUsePCH(true), SuppressMissingInputWarning(false) {
59 
60   Name = llvm::sys::path::filename(ClangExecutable);
61   Dir = llvm::sys::path::parent_path(ClangExecutable);
62 
63   // Compute the path to the resource directory.
64   StringRef ClangResourceDir(CLANG_RESOURCE_DIR);
65   SmallString<128> P(Dir);
66   if (ClangResourceDir != "") {
67     llvm::sys::path::append(P, ClangResourceDir);
68   } else {
69     StringRef ClangLibdirSuffix(CLANG_LIBDIR_SUFFIX);
70     llvm::sys::path::append(P, "..", Twine("lib") + ClangLibdirSuffix, "clang",
71                             CLANG_VERSION_STRING);
72   }
73   ResourceDir = P.str();
74 }
75 
76 Driver::~Driver() {
77   delete Opts;
78 
79   llvm::DeleteContainerSeconds(ToolChains);
80 }
81 
82 void Driver::ParseDriverMode(ArrayRef<const char *> Args) {
83   const std::string OptName =
84       getOpts().getOption(options::OPT_driver_mode).getPrefixedName();
85 
86   for (const char *ArgPtr : Args) {
87     // Ingore nullptrs, they are response file's EOL markers
88     if (ArgPtr == nullptr)
89       continue;
90     const StringRef Arg = ArgPtr;
91     if (!Arg.startswith(OptName))
92       continue;
93 
94     const StringRef Value = Arg.drop_front(OptName.size());
95     const unsigned M = llvm::StringSwitch<unsigned>(Value)
96                            .Case("gcc", GCCMode)
97                            .Case("g++", GXXMode)
98                            .Case("cpp", CPPMode)
99                            .Case("cl", CLMode)
100                            .Default(~0U);
101 
102     if (M != ~0U)
103       Mode = static_cast<DriverMode>(M);
104     else
105       Diag(diag::err_drv_unsupported_option_argument) << OptName << Value;
106   }
107 }
108 
109 InputArgList Driver::ParseArgStrings(ArrayRef<const char *> ArgStrings) {
110   llvm::PrettyStackTraceString CrashInfo("Command line argument parsing");
111 
112   unsigned IncludedFlagsBitmask;
113   unsigned ExcludedFlagsBitmask;
114   std::tie(IncludedFlagsBitmask, ExcludedFlagsBitmask) =
115       getIncludeExcludeOptionFlagMasks();
116 
117   unsigned MissingArgIndex, MissingArgCount;
118   InputArgList Args =
119       getOpts().ParseArgs(ArgStrings, MissingArgIndex, MissingArgCount,
120                           IncludedFlagsBitmask, ExcludedFlagsBitmask);
121 
122   // Check for missing argument error.
123   if (MissingArgCount)
124     Diag(clang::diag::err_drv_missing_argument)
125         << Args.getArgString(MissingArgIndex) << MissingArgCount;
126 
127   // Check for unsupported options.
128   for (const Arg *A : Args) {
129     if (A->getOption().hasFlag(options::Unsupported)) {
130       Diag(clang::diag::err_drv_unsupported_opt) << A->getAsString(Args);
131       continue;
132     }
133 
134     // Warn about -mcpu= without an argument.
135     if (A->getOption().matches(options::OPT_mcpu_EQ) && A->containsValue("")) {
136       Diag(clang::diag::warn_drv_empty_joined_argument) << A->getAsString(Args);
137     }
138   }
139 
140   for (const Arg *A : Args.filtered(options::OPT_UNKNOWN))
141     Diags.Report(diag::err_drv_unknown_argument) << A->getAsString(Args);
142 
143   return Args;
144 }
145 
146 // Determine which compilation mode we are in. We look for options which
147 // affect the phase, starting with the earliest phases, and record which
148 // option we used to determine the final phase.
149 phases::ID Driver::getFinalPhase(const DerivedArgList &DAL,
150                                  Arg **FinalPhaseArg) const {
151   Arg *PhaseArg = nullptr;
152   phases::ID FinalPhase;
153 
154   // -{E,EP,P,M,MM} only run the preprocessor.
155   if (CCCIsCPP() || (PhaseArg = DAL.getLastArg(options::OPT_E)) ||
156       (PhaseArg = DAL.getLastArg(options::OPT__SLASH_EP)) ||
157       (PhaseArg = DAL.getLastArg(options::OPT_M, options::OPT_MM)) ||
158       (PhaseArg = DAL.getLastArg(options::OPT__SLASH_P))) {
159     FinalPhase = phases::Preprocess;
160 
161     // -{fsyntax-only,-analyze,emit-ast} only run up to the compiler.
162   } else if ((PhaseArg = DAL.getLastArg(options::OPT_fsyntax_only)) ||
163              (PhaseArg = DAL.getLastArg(options::OPT_module_file_info)) ||
164              (PhaseArg = DAL.getLastArg(options::OPT_verify_pch)) ||
165              (PhaseArg = DAL.getLastArg(options::OPT_rewrite_objc)) ||
166              (PhaseArg = DAL.getLastArg(options::OPT_rewrite_legacy_objc)) ||
167              (PhaseArg = DAL.getLastArg(options::OPT__migrate)) ||
168              (PhaseArg = DAL.getLastArg(options::OPT__analyze,
169                                         options::OPT__analyze_auto)) ||
170              (PhaseArg = DAL.getLastArg(options::OPT_emit_ast))) {
171     FinalPhase = phases::Compile;
172 
173     // -S only runs up to the backend.
174   } else if ((PhaseArg = DAL.getLastArg(options::OPT_S))) {
175     FinalPhase = phases::Backend;
176 
177     // -c compilation only runs up to the assembler.
178   } else if ((PhaseArg = DAL.getLastArg(options::OPT_c))) {
179     FinalPhase = phases::Assemble;
180 
181     // Otherwise do everything.
182   } else
183     FinalPhase = phases::Link;
184 
185   if (FinalPhaseArg)
186     *FinalPhaseArg = PhaseArg;
187 
188   return FinalPhase;
189 }
190 
191 static Arg *MakeInputArg(DerivedArgList &Args, OptTable *Opts,
192                          StringRef Value) {
193   Arg *A = new Arg(Opts->getOption(options::OPT_INPUT), Value,
194                    Args.getBaseArgs().MakeIndex(Value), Value.data());
195   Args.AddSynthesizedArg(A);
196   A->claim();
197   return A;
198 }
199 
200 DerivedArgList *Driver::TranslateInputArgs(const InputArgList &Args) const {
201   DerivedArgList *DAL = new DerivedArgList(Args);
202 
203   bool HasNostdlib = Args.hasArg(options::OPT_nostdlib);
204   for (Arg *A : Args) {
205     // Unfortunately, we have to parse some forwarding options (-Xassembler,
206     // -Xlinker, -Xpreprocessor) because we either integrate their functionality
207     // (assembler and preprocessor), or bypass a previous driver ('collect2').
208 
209     // Rewrite linker options, to replace --no-demangle with a custom internal
210     // option.
211     if ((A->getOption().matches(options::OPT_Wl_COMMA) ||
212          A->getOption().matches(options::OPT_Xlinker)) &&
213         A->containsValue("--no-demangle")) {
214       // Add the rewritten no-demangle argument.
215       DAL->AddFlagArg(A, Opts->getOption(options::OPT_Z_Xlinker__no_demangle));
216 
217       // Add the remaining values as Xlinker arguments.
218       for (const StringRef Val : A->getValues())
219         if (Val != "--no-demangle")
220           DAL->AddSeparateArg(A, Opts->getOption(options::OPT_Xlinker), Val);
221 
222       continue;
223     }
224 
225     // Rewrite preprocessor options, to replace -Wp,-MD,FOO which is used by
226     // some build systems. We don't try to be complete here because we don't
227     // care to encourage this usage model.
228     if (A->getOption().matches(options::OPT_Wp_COMMA) &&
229         (A->getValue(0) == StringRef("-MD") ||
230          A->getValue(0) == StringRef("-MMD"))) {
231       // Rewrite to -MD/-MMD along with -MF.
232       if (A->getValue(0) == StringRef("-MD"))
233         DAL->AddFlagArg(A, Opts->getOption(options::OPT_MD));
234       else
235         DAL->AddFlagArg(A, Opts->getOption(options::OPT_MMD));
236       if (A->getNumValues() == 2)
237         DAL->AddSeparateArg(A, Opts->getOption(options::OPT_MF),
238                             A->getValue(1));
239       continue;
240     }
241 
242     // Rewrite reserved library names.
243     if (A->getOption().matches(options::OPT_l)) {
244       StringRef Value = A->getValue();
245 
246       // Rewrite unless -nostdlib is present.
247       if (!HasNostdlib && Value == "stdc++") {
248         DAL->AddFlagArg(A, Opts->getOption(options::OPT_Z_reserved_lib_stdcxx));
249         continue;
250       }
251 
252       // Rewrite unconditionally.
253       if (Value == "cc_kext") {
254         DAL->AddFlagArg(A, Opts->getOption(options::OPT_Z_reserved_lib_cckext));
255         continue;
256       }
257     }
258 
259     // Pick up inputs via the -- option.
260     if (A->getOption().matches(options::OPT__DASH_DASH)) {
261       A->claim();
262       for (const StringRef Val : A->getValues())
263         DAL->append(MakeInputArg(*DAL, Opts, Val));
264       continue;
265     }
266 
267     DAL->append(A);
268   }
269 
270 // Add a default value of -mlinker-version=, if one was given and the user
271 // didn't specify one.
272 #if defined(HOST_LINK_VERSION)
273   if (!Args.hasArg(options::OPT_mlinker_version_EQ) &&
274       strlen(HOST_LINK_VERSION) > 0) {
275     DAL->AddJoinedArg(0, Opts->getOption(options::OPT_mlinker_version_EQ),
276                       HOST_LINK_VERSION);
277     DAL->getLastArg(options::OPT_mlinker_version_EQ)->claim();
278   }
279 #endif
280 
281   return DAL;
282 }
283 
284 /// \brief Compute target triple from args.
285 ///
286 /// This routine provides the logic to compute a target triple from various
287 /// args passed to the driver and the default triple string.
288 static llvm::Triple computeTargetTriple(StringRef DefaultTargetTriple,
289                                         const ArgList &Args,
290                                         StringRef DarwinArchName = "") {
291   // FIXME: Already done in Compilation *Driver::BuildCompilation
292   if (const Arg *A = Args.getLastArg(options::OPT_target))
293     DefaultTargetTriple = A->getValue();
294 
295   llvm::Triple Target(llvm::Triple::normalize(DefaultTargetTriple));
296 
297   // Handle Apple-specific options available here.
298   if (Target.isOSBinFormatMachO()) {
299     // If an explict Darwin arch name is given, that trumps all.
300     if (!DarwinArchName.empty()) {
301       tools::darwin::setTripleTypeForMachOArchName(Target, DarwinArchName);
302       return Target;
303     }
304 
305     // Handle the Darwin '-arch' flag.
306     if (Arg *A = Args.getLastArg(options::OPT_arch)) {
307       StringRef ArchName = A->getValue();
308       tools::darwin::setTripleTypeForMachOArchName(Target, ArchName);
309     }
310   }
311 
312   // Handle pseudo-target flags '-mlittle-endian'/'-EL' and
313   // '-mbig-endian'/'-EB'.
314   if (Arg *A = Args.getLastArg(options::OPT_mlittle_endian,
315                                options::OPT_mbig_endian)) {
316     if (A->getOption().matches(options::OPT_mlittle_endian)) {
317       llvm::Triple LE = Target.getLittleEndianArchVariant();
318       if (LE.getArch() != llvm::Triple::UnknownArch)
319         Target = std::move(LE);
320     } else {
321       llvm::Triple BE = Target.getBigEndianArchVariant();
322       if (BE.getArch() != llvm::Triple::UnknownArch)
323         Target = std::move(BE);
324     }
325   }
326 
327   // Skip further flag support on OSes which don't support '-m32' or '-m64'.
328   if (Target.getArch() == llvm::Triple::tce ||
329       Target.getOS() == llvm::Triple::Minix)
330     return Target;
331 
332   // Handle pseudo-target flags '-m64', '-mx32', '-m32' and '-m16'.
333   if (Arg *A = Args.getLastArg(options::OPT_m64, options::OPT_mx32,
334                                options::OPT_m32, options::OPT_m16)) {
335     llvm::Triple::ArchType AT = llvm::Triple::UnknownArch;
336 
337     if (A->getOption().matches(options::OPT_m64)) {
338       AT = Target.get64BitArchVariant().getArch();
339       if (Target.getEnvironment() == llvm::Triple::GNUX32)
340         Target.setEnvironment(llvm::Triple::GNU);
341     } else if (A->getOption().matches(options::OPT_mx32) &&
342                Target.get64BitArchVariant().getArch() == llvm::Triple::x86_64) {
343       AT = llvm::Triple::x86_64;
344       Target.setEnvironment(llvm::Triple::GNUX32);
345     } else if (A->getOption().matches(options::OPT_m32)) {
346       AT = Target.get32BitArchVariant().getArch();
347       if (Target.getEnvironment() == llvm::Triple::GNUX32)
348         Target.setEnvironment(llvm::Triple::GNU);
349     } else if (A->getOption().matches(options::OPT_m16) &&
350                Target.get32BitArchVariant().getArch() == llvm::Triple::x86) {
351       AT = llvm::Triple::x86;
352       Target.setEnvironment(llvm::Triple::CODE16);
353     }
354 
355     if (AT != llvm::Triple::UnknownArch && AT != Target.getArch())
356       Target.setArch(AT);
357   }
358 
359   return Target;
360 }
361 
362 Compilation *Driver::BuildCompilation(ArrayRef<const char *> ArgList) {
363   llvm::PrettyStackTraceString CrashInfo("Compilation construction");
364 
365   // FIXME: Handle environment options which affect driver behavior, somewhere
366   // (client?). GCC_EXEC_PREFIX, LPATH, CC_PRINT_OPTIONS.
367 
368   if (char *env = ::getenv("COMPILER_PATH")) {
369     StringRef CompilerPath = env;
370     while (!CompilerPath.empty()) {
371       std::pair<StringRef, StringRef> Split =
372           CompilerPath.split(llvm::sys::EnvPathSeparator);
373       PrefixDirs.push_back(Split.first);
374       CompilerPath = Split.second;
375     }
376   }
377 
378   // We look for the driver mode option early, because the mode can affect
379   // how other options are parsed.
380   ParseDriverMode(ArgList.slice(1));
381 
382   // FIXME: What are we going to do with -V and -b?
383 
384   // FIXME: This stuff needs to go into the Compilation, not the driver.
385   bool CCCPrintPhases;
386 
387   InputArgList Args = ParseArgStrings(ArgList.slice(1));
388 
389   // Silence driver warnings if requested
390   Diags.setIgnoreAllWarnings(Args.hasArg(options::OPT_w));
391 
392   // -no-canonical-prefixes is used very early in main.
393   Args.ClaimAllArgs(options::OPT_no_canonical_prefixes);
394 
395   // Ignore -pipe.
396   Args.ClaimAllArgs(options::OPT_pipe);
397 
398   // Extract -ccc args.
399   //
400   // FIXME: We need to figure out where this behavior should live. Most of it
401   // should be outside in the client; the parts that aren't should have proper
402   // options, either by introducing new ones or by overloading gcc ones like -V
403   // or -b.
404   CCCPrintPhases = Args.hasArg(options::OPT_ccc_print_phases);
405   CCCPrintBindings = Args.hasArg(options::OPT_ccc_print_bindings);
406   if (const Arg *A = Args.getLastArg(options::OPT_ccc_gcc_name))
407     CCCGenericGCCName = A->getValue();
408   CCCUsePCH =
409       Args.hasFlag(options::OPT_ccc_pch_is_pch, options::OPT_ccc_pch_is_pth);
410   // FIXME: DefaultTargetTriple is used by the target-prefixed calls to as/ld
411   // and getToolChain is const.
412   if (IsCLMode()) {
413     // clang-cl targets MSVC-style Win32.
414     llvm::Triple T(DefaultTargetTriple);
415     T.setOS(llvm::Triple::Win32);
416     T.setVendor(llvm::Triple::PC);
417     T.setEnvironment(llvm::Triple::MSVC);
418     DefaultTargetTriple = T.str();
419   }
420   if (const Arg *A = Args.getLastArg(options::OPT_target))
421     DefaultTargetTriple = A->getValue();
422   if (const Arg *A = Args.getLastArg(options::OPT_ccc_install_dir))
423     Dir = InstalledDir = A->getValue();
424   for (const Arg *A : Args.filtered(options::OPT_B)) {
425     A->claim();
426     PrefixDirs.push_back(A->getValue(0));
427   }
428   if (const Arg *A = Args.getLastArg(options::OPT__sysroot_EQ))
429     SysRoot = A->getValue();
430   if (const Arg *A = Args.getLastArg(options::OPT__dyld_prefix_EQ))
431     DyldPrefix = A->getValue();
432   if (Args.hasArg(options::OPT_nostdlib))
433     UseStdLib = false;
434 
435   if (const Arg *A = Args.getLastArg(options::OPT_resource_dir))
436     ResourceDir = A->getValue();
437 
438   if (const Arg *A = Args.getLastArg(options::OPT_save_temps_EQ)) {
439     SaveTemps = llvm::StringSwitch<SaveTempsMode>(A->getValue())
440                     .Case("cwd", SaveTempsCwd)
441                     .Case("obj", SaveTempsObj)
442                     .Default(SaveTempsCwd);
443   }
444 
445   std::unique_ptr<llvm::opt::InputArgList> UArgs =
446       llvm::make_unique<InputArgList>(std::move(Args));
447 
448   // Perform the default argument translations.
449   DerivedArgList *TranslatedArgs = TranslateInputArgs(*UArgs);
450 
451   // Owned by the host.
452   const ToolChain &TC =
453       getToolChain(*UArgs, computeTargetTriple(DefaultTargetTriple, *UArgs));
454 
455   // The compilation takes ownership of Args.
456   Compilation *C = new Compilation(*this, TC, UArgs.release(), TranslatedArgs);
457 
458   if (!HandleImmediateArgs(*C))
459     return C;
460 
461   // Construct the list of inputs.
462   InputList Inputs;
463   BuildInputs(C->getDefaultToolChain(), *TranslatedArgs, Inputs);
464 
465   // Construct the list of abstract actions to perform for this compilation. On
466   // MachO targets this uses the driver-driver and universal actions.
467   if (TC.getTriple().isOSBinFormatMachO())
468     BuildUniversalActions(C->getDefaultToolChain(), C->getArgs(), Inputs,
469                           C->getActions());
470   else
471     BuildActions(C->getDefaultToolChain(), C->getArgs(), Inputs,
472                  C->getActions());
473 
474   if (CCCPrintPhases) {
475     PrintActions(*C);
476     return C;
477   }
478 
479   BuildJobs(*C);
480 
481   return C;
482 }
483 
484 static void printArgList(raw_ostream &OS, const llvm::opt::ArgList &Args) {
485   llvm::opt::ArgStringList ASL;
486   for (const auto *A : Args)
487     A->render(Args, ASL);
488 
489   for (auto I = ASL.begin(), E = ASL.end(); I != E; ++I) {
490     if (I != ASL.begin())
491       OS << ' ';
492     Command::printArg(OS, *I, true);
493   }
494   OS << '\n';
495 }
496 
497 // When clang crashes, produce diagnostic information including the fully
498 // preprocessed source file(s).  Request that the developer attach the
499 // diagnostic information to a bug report.
500 void Driver::generateCompilationDiagnostics(Compilation &C,
501                                             const Command &FailingCommand) {
502   if (C.getArgs().hasArg(options::OPT_fno_crash_diagnostics))
503     return;
504 
505   // Don't try to generate diagnostics for link or dsymutil jobs.
506   if (FailingCommand.getCreator().isLinkJob() ||
507       FailingCommand.getCreator().isDsymutilJob())
508     return;
509 
510   // Print the version of the compiler.
511   PrintVersion(C, llvm::errs());
512 
513   Diag(clang::diag::note_drv_command_failed_diag_msg)
514       << "PLEASE submit a bug report to " BUG_REPORT_URL " and include the "
515          "crash backtrace, preprocessed source, and associated run script.";
516 
517   // Suppress driver output and emit preprocessor output to temp file.
518   Mode = CPPMode;
519   CCGenDiagnostics = true;
520 
521   // Save the original job command(s).
522   Command Cmd = FailingCommand;
523 
524   // Keep track of whether we produce any errors while trying to produce
525   // preprocessed sources.
526   DiagnosticErrorTrap Trap(Diags);
527 
528   // Suppress tool output.
529   C.initCompilationForDiagnostics();
530 
531   // Construct the list of inputs.
532   InputList Inputs;
533   BuildInputs(C.getDefaultToolChain(), C.getArgs(), Inputs);
534 
535   for (InputList::iterator it = Inputs.begin(), ie = Inputs.end(); it != ie;) {
536     bool IgnoreInput = false;
537 
538     // Ignore input from stdin or any inputs that cannot be preprocessed.
539     // Check type first as not all linker inputs have a value.
540     if (types::getPreprocessedType(it->first) == types::TY_INVALID) {
541       IgnoreInput = true;
542     } else if (!strcmp(it->second->getValue(), "-")) {
543       Diag(clang::diag::note_drv_command_failed_diag_msg)
544           << "Error generating preprocessed source(s) - "
545              "ignoring input from stdin.";
546       IgnoreInput = true;
547     }
548 
549     if (IgnoreInput) {
550       it = Inputs.erase(it);
551       ie = Inputs.end();
552     } else {
553       ++it;
554     }
555   }
556 
557   if (Inputs.empty()) {
558     Diag(clang::diag::note_drv_command_failed_diag_msg)
559         << "Error generating preprocessed source(s) - "
560            "no preprocessable inputs.";
561     return;
562   }
563 
564   // Don't attempt to generate preprocessed files if multiple -arch options are
565   // used, unless they're all duplicates.
566   llvm::StringSet<> ArchNames;
567   for (const Arg *A : C.getArgs()) {
568     if (A->getOption().matches(options::OPT_arch)) {
569       StringRef ArchName = A->getValue();
570       ArchNames.insert(ArchName);
571     }
572   }
573   if (ArchNames.size() > 1) {
574     Diag(clang::diag::note_drv_command_failed_diag_msg)
575         << "Error generating preprocessed source(s) - cannot generate "
576            "preprocessed source with multiple -arch options.";
577     return;
578   }
579 
580   // Construct the list of abstract actions to perform for this compilation. On
581   // Darwin OSes this uses the driver-driver and builds universal actions.
582   const ToolChain &TC = C.getDefaultToolChain();
583   if (TC.getTriple().isOSBinFormatMachO())
584     BuildUniversalActions(TC, C.getArgs(), Inputs, C.getActions());
585   else
586     BuildActions(TC, C.getArgs(), Inputs, C.getActions());
587 
588   BuildJobs(C);
589 
590   // If there were errors building the compilation, quit now.
591   if (Trap.hasErrorOccurred()) {
592     Diag(clang::diag::note_drv_command_failed_diag_msg)
593         << "Error generating preprocessed source(s).";
594     return;
595   }
596 
597   // Generate preprocessed output.
598   SmallVector<std::pair<int, const Command *>, 4> FailingCommands;
599   C.ExecuteJobs(C.getJobs(), FailingCommands);
600 
601   // If any of the preprocessing commands failed, clean up and exit.
602   if (!FailingCommands.empty()) {
603     if (!isSaveTempsEnabled())
604       C.CleanupFileList(C.getTempFiles(), true);
605 
606     Diag(clang::diag::note_drv_command_failed_diag_msg)
607         << "Error generating preprocessed source(s).";
608     return;
609   }
610 
611   const ArgStringList &TempFiles = C.getTempFiles();
612   if (TempFiles.empty()) {
613     Diag(clang::diag::note_drv_command_failed_diag_msg)
614         << "Error generating preprocessed source(s).";
615     return;
616   }
617 
618   Diag(clang::diag::note_drv_command_failed_diag_msg)
619       << "\n********************\n\n"
620          "PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:\n"
621          "Preprocessed source(s) and associated run script(s) are located at:";
622 
623   SmallString<128> VFS;
624   for (const char *TempFile : TempFiles) {
625     Diag(clang::diag::note_drv_command_failed_diag_msg) << TempFile;
626     if (StringRef(TempFile).endswith(".cache")) {
627       // In some cases (modules) we'll dump extra data to help with reproducing
628       // the crash into a directory next to the output.
629       VFS = llvm::sys::path::filename(TempFile);
630       llvm::sys::path::append(VFS, "vfs", "vfs.yaml");
631     }
632   }
633 
634   // Assume associated files are based off of the first temporary file.
635   CrashReportInfo CrashInfo(TempFiles[0], VFS);
636 
637   std::string Script = CrashInfo.Filename.rsplit('.').first.str() + ".sh";
638   std::error_code EC;
639   llvm::raw_fd_ostream ScriptOS(Script, EC, llvm::sys::fs::F_Excl);
640   if (EC) {
641     Diag(clang::diag::note_drv_command_failed_diag_msg)
642         << "Error generating run script: " + Script + " " + EC.message();
643   } else {
644     ScriptOS << "# Crash reproducer for " << getClangFullVersion() << "\n"
645              << "# Driver args: ";
646     printArgList(ScriptOS, C.getInputArgs());
647     ScriptOS << "# Original command: ";
648     Cmd.Print(ScriptOS, "\n", /*Quote=*/true);
649     Cmd.Print(ScriptOS, "\n", /*Quote=*/true, &CrashInfo);
650     Diag(clang::diag::note_drv_command_failed_diag_msg) << Script;
651   }
652 
653   for (const auto &A : C.getArgs().filtered(options::OPT_frewrite_map_file,
654                                             options::OPT_frewrite_map_file_EQ))
655     Diag(clang::diag::note_drv_command_failed_diag_msg) << A->getValue();
656 
657   Diag(clang::diag::note_drv_command_failed_diag_msg)
658       << "\n\n********************";
659 }
660 
661 void Driver::setUpResponseFiles(Compilation &C, Command &Cmd) {
662   // Since argumentsFitWithinSystemLimits() may underestimate system's capacity
663   // if the tool does not support response files, there is a chance/ that things
664   // will just work without a response file, so we silently just skip it.
665   if (Cmd.getCreator().getResponseFilesSupport() == Tool::RF_None ||
666       llvm::sys::argumentsFitWithinSystemLimits(Cmd.getArguments()))
667     return;
668 
669   std::string TmpName = GetTemporaryPath("response", "txt");
670   Cmd.setResponseFile(
671       C.addTempFile(C.getArgs().MakeArgString(TmpName.c_str())));
672 }
673 
674 int Driver::ExecuteCompilation(
675     Compilation &C,
676     SmallVectorImpl<std::pair<int, const Command *>> &FailingCommands) {
677   // Just print if -### was present.
678   if (C.getArgs().hasArg(options::OPT__HASH_HASH_HASH)) {
679     C.getJobs().Print(llvm::errs(), "\n", true);
680     return 0;
681   }
682 
683   // If there were errors building the compilation, quit now.
684   if (Diags.hasErrorOccurred())
685     return 1;
686 
687   // Set up response file names for each command, if necessary
688   for (auto &Job : C.getJobs())
689     setUpResponseFiles(C, Job);
690 
691   C.ExecuteJobs(C.getJobs(), FailingCommands);
692 
693   // Remove temp files.
694   C.CleanupFileList(C.getTempFiles());
695 
696   // If the command succeeded, we are done.
697   if (FailingCommands.empty())
698     return 0;
699 
700   // Otherwise, remove result files and print extra information about abnormal
701   // failures.
702   for (const auto &CmdPair : FailingCommands) {
703     int Res = CmdPair.first;
704     const Command *FailingCommand = CmdPair.second;
705 
706     // Remove result files if we're not saving temps.
707     if (!isSaveTempsEnabled()) {
708       const JobAction *JA = cast<JobAction>(&FailingCommand->getSource());
709       C.CleanupFileMap(C.getResultFiles(), JA, true);
710 
711       // Failure result files are valid unless we crashed.
712       if (Res < 0)
713         C.CleanupFileMap(C.getFailureResultFiles(), JA, true);
714     }
715 
716     // Print extra information about abnormal failures, if possible.
717     //
718     // This is ad-hoc, but we don't want to be excessively noisy. If the result
719     // status was 1, assume the command failed normally. In particular, if it
720     // was the compiler then assume it gave a reasonable error code. Failures
721     // in other tools are less common, and they generally have worse
722     // diagnostics, so always print the diagnostic there.
723     const Tool &FailingTool = FailingCommand->getCreator();
724 
725     if (!FailingCommand->getCreator().hasGoodDiagnostics() || Res != 1) {
726       // FIXME: See FIXME above regarding result code interpretation.
727       if (Res < 0)
728         Diag(clang::diag::err_drv_command_signalled)
729             << FailingTool.getShortName();
730       else
731         Diag(clang::diag::err_drv_command_failed) << FailingTool.getShortName()
732                                                   << Res;
733     }
734   }
735   return 0;
736 }
737 
738 void Driver::PrintHelp(bool ShowHidden) const {
739   unsigned IncludedFlagsBitmask;
740   unsigned ExcludedFlagsBitmask;
741   std::tie(IncludedFlagsBitmask, ExcludedFlagsBitmask) =
742       getIncludeExcludeOptionFlagMasks();
743 
744   ExcludedFlagsBitmask |= options::NoDriverOption;
745   if (!ShowHidden)
746     ExcludedFlagsBitmask |= HelpHidden;
747 
748   getOpts().PrintHelp(llvm::outs(), Name.c_str(), DriverTitle.c_str(),
749                       IncludedFlagsBitmask, ExcludedFlagsBitmask);
750 }
751 
752 void Driver::PrintVersion(const Compilation &C, raw_ostream &OS) const {
753   // FIXME: The following handlers should use a callback mechanism, we don't
754   // know what the client would like to do.
755   OS << getClangFullVersion() << '\n';
756   const ToolChain &TC = C.getDefaultToolChain();
757   OS << "Target: " << TC.getTripleString() << '\n';
758 
759   // Print the threading model.
760   if (Arg *A = C.getArgs().getLastArg(options::OPT_mthread_model)) {
761     // Don't print if the ToolChain would have barfed on it already
762     if (TC.isThreadModelSupported(A->getValue()))
763       OS << "Thread model: " << A->getValue();
764   } else
765     OS << "Thread model: " << TC.getThreadModel();
766   OS << '\n';
767 
768   // Print out the install directory.
769   OS << "InstalledDir: " << InstalledDir << '\n';
770 }
771 
772 /// PrintDiagnosticCategories - Implement the --print-diagnostic-categories
773 /// option.
774 static void PrintDiagnosticCategories(raw_ostream &OS) {
775   // Skip the empty category.
776   for (unsigned i = 1, max = DiagnosticIDs::getNumberOfCategories(); i != max;
777        ++i)
778     OS << i << ',' << DiagnosticIDs::getCategoryNameFromID(i) << '\n';
779 }
780 
781 bool Driver::HandleImmediateArgs(const Compilation &C) {
782   // The order these options are handled in gcc is all over the place, but we
783   // don't expect inconsistencies w.r.t. that to matter in practice.
784 
785   if (C.getArgs().hasArg(options::OPT_dumpmachine)) {
786     llvm::outs() << C.getDefaultToolChain().getTripleString() << '\n';
787     return false;
788   }
789 
790   if (C.getArgs().hasArg(options::OPT_dumpversion)) {
791     // Since -dumpversion is only implemented for pedantic GCC compatibility, we
792     // return an answer which matches our definition of __VERSION__.
793     //
794     // If we want to return a more correct answer some day, then we should
795     // introduce a non-pedantically GCC compatible mode to Clang in which we
796     // provide sensible definitions for -dumpversion, __VERSION__, etc.
797     llvm::outs() << "4.2.1\n";
798     return false;
799   }
800 
801   if (C.getArgs().hasArg(options::OPT__print_diagnostic_categories)) {
802     PrintDiagnosticCategories(llvm::outs());
803     return false;
804   }
805 
806   if (C.getArgs().hasArg(options::OPT_help) ||
807       C.getArgs().hasArg(options::OPT__help_hidden)) {
808     PrintHelp(C.getArgs().hasArg(options::OPT__help_hidden));
809     return false;
810   }
811 
812   if (C.getArgs().hasArg(options::OPT__version)) {
813     // Follow gcc behavior and use stdout for --version and stderr for -v.
814     PrintVersion(C, llvm::outs());
815     return false;
816   }
817 
818   if (C.getArgs().hasArg(options::OPT_v) ||
819       C.getArgs().hasArg(options::OPT__HASH_HASH_HASH)) {
820     PrintVersion(C, llvm::errs());
821     SuppressMissingInputWarning = true;
822   }
823 
824   const ToolChain &TC = C.getDefaultToolChain();
825 
826   if (C.getArgs().hasArg(options::OPT_v))
827     TC.printVerboseInfo(llvm::errs());
828 
829   if (C.getArgs().hasArg(options::OPT_print_search_dirs)) {
830     llvm::outs() << "programs: =";
831     bool separator = false;
832     for (const std::string &Path : TC.getProgramPaths()) {
833       if (separator)
834         llvm::outs() << ':';
835       llvm::outs() << Path;
836       separator = true;
837     }
838     llvm::outs() << "\n";
839     llvm::outs() << "libraries: =" << ResourceDir;
840 
841     StringRef sysroot = C.getSysRoot();
842 
843     for (const std::string &Path : TC.getFilePaths()) {
844       // Always print a separator. ResourceDir was the first item shown.
845       llvm::outs() << ':';
846       // Interpretation of leading '=' is needed only for NetBSD.
847       if (Path[0] == '=')
848         llvm::outs() << sysroot << Path.substr(1);
849       else
850         llvm::outs() << Path;
851     }
852     llvm::outs() << "\n";
853     return false;
854   }
855 
856   // FIXME: The following handlers should use a callback mechanism, we don't
857   // know what the client would like to do.
858   if (Arg *A = C.getArgs().getLastArg(options::OPT_print_file_name_EQ)) {
859     llvm::outs() << GetFilePath(A->getValue(), TC) << "\n";
860     return false;
861   }
862 
863   if (Arg *A = C.getArgs().getLastArg(options::OPT_print_prog_name_EQ)) {
864     llvm::outs() << GetProgramPath(A->getValue(), TC) << "\n";
865     return false;
866   }
867 
868   if (C.getArgs().hasArg(options::OPT_print_libgcc_file_name)) {
869     llvm::outs() << GetFilePath("libgcc.a", TC) << "\n";
870     return false;
871   }
872 
873   if (C.getArgs().hasArg(options::OPT_print_multi_lib)) {
874     for (const Multilib &Multilib : TC.getMultilibs())
875       llvm::outs() << Multilib << "\n";
876     return false;
877   }
878 
879   if (C.getArgs().hasArg(options::OPT_print_multi_directory)) {
880     for (const Multilib &Multilib : TC.getMultilibs()) {
881       if (Multilib.gccSuffix().empty())
882         llvm::outs() << ".\n";
883       else {
884         StringRef Suffix(Multilib.gccSuffix());
885         assert(Suffix.front() == '/');
886         llvm::outs() << Suffix.substr(1) << "\n";
887       }
888     }
889     return false;
890   }
891   return true;
892 }
893 
894 // Display an action graph human-readably.  Action A is the "sink" node
895 // and latest-occuring action. Traversal is in pre-order, visiting the
896 // inputs to each action before printing the action itself.
897 static unsigned PrintActions1(const Compilation &C, Action *A,
898                               std::map<Action *, unsigned> &Ids) {
899   if (Ids.count(A)) // A was already visited.
900     return Ids[A];
901 
902   std::string str;
903   llvm::raw_string_ostream os(str);
904 
905   os << Action::getClassName(A->getKind()) << ", ";
906   if (InputAction *IA = dyn_cast<InputAction>(A)) {
907     os << "\"" << IA->getInputArg().getValue() << "\"";
908   } else if (BindArchAction *BIA = dyn_cast<BindArchAction>(A)) {
909     os << '"' << BIA->getArchName() << '"' << ", {"
910        << PrintActions1(C, *BIA->begin(), Ids) << "}";
911   } else if (CudaDeviceAction *CDA = dyn_cast<CudaDeviceAction>(A)) {
912     os << '"' << CDA->getGpuArchName() << '"' << ", {"
913        << PrintActions1(C, *CDA->begin(), Ids) << "}";
914   } else {
915     ActionList *AL;
916     if (CudaHostAction *CHA = dyn_cast<CudaHostAction>(A)) {
917       os << "{" << PrintActions1(C, *CHA->begin(), Ids) << "}"
918          << ", gpu binaries ";
919       AL = &CHA->getDeviceActions();
920     } else
921       AL = &A->getInputs();
922 
923     const char *Prefix = "{";
924     for (Action *PreRequisite : *AL) {
925       os << Prefix << PrintActions1(C, PreRequisite, Ids);
926       Prefix = ", ";
927     }
928     os << "}";
929   }
930 
931   unsigned Id = Ids.size();
932   Ids[A] = Id;
933   llvm::errs() << Id << ": " << os.str() << ", "
934                << types::getTypeName(A->getType()) << "\n";
935 
936   return Id;
937 }
938 
939 // Print the action graphs in a compilation C.
940 // For example "clang -c file1.c file2.c" is composed of two subgraphs.
941 void Driver::PrintActions(const Compilation &C) const {
942   std::map<Action *, unsigned> Ids;
943   for (Action *A : C.getActions())
944     PrintActions1(C, A, Ids);
945 }
946 
947 /// \brief Check whether the given input tree contains any compilation or
948 /// assembly actions.
949 static bool ContainsCompileOrAssembleAction(const Action *A) {
950   if (isa<CompileJobAction>(A) || isa<BackendJobAction>(A) ||
951       isa<AssembleJobAction>(A))
952     return true;
953 
954   for (Action::const_iterator it = A->begin(), ie = A->end(); it != ie; ++it)
955     if (ContainsCompileOrAssembleAction(*it))
956       return true;
957 
958   return false;
959 }
960 
961 void Driver::BuildUniversalActions(const ToolChain &TC, DerivedArgList &Args,
962                                    const InputList &BAInputs,
963                                    ActionList &Actions) const {
964   llvm::PrettyStackTraceString CrashInfo("Building universal build actions");
965   // Collect the list of architectures. Duplicates are allowed, but should only
966   // be handled once (in the order seen).
967   llvm::StringSet<> ArchNames;
968   SmallVector<const char *, 4> Archs;
969   for (Arg *A : Args) {
970     if (A->getOption().matches(options::OPT_arch)) {
971       // Validate the option here; we don't save the type here because its
972       // particular spelling may participate in other driver choices.
973       llvm::Triple::ArchType Arch =
974           tools::darwin::getArchTypeForMachOArchName(A->getValue());
975       if (Arch == llvm::Triple::UnknownArch) {
976         Diag(clang::diag::err_drv_invalid_arch_name) << A->getAsString(Args);
977         continue;
978       }
979 
980       A->claim();
981       if (ArchNames.insert(A->getValue()).second)
982         Archs.push_back(A->getValue());
983     }
984   }
985 
986   // When there is no explicit arch for this platform, make sure we still bind
987   // the architecture (to the default) so that -Xarch_ is handled correctly.
988   if (!Archs.size())
989     Archs.push_back(Args.MakeArgString(TC.getDefaultUniversalArchName()));
990 
991   ActionList SingleActions;
992   BuildActions(TC, Args, BAInputs, SingleActions);
993 
994   // Add in arch bindings for every top level action, as well as lipo and
995   // dsymutil steps if needed.
996   for (unsigned i = 0, e = SingleActions.size(); i != e; ++i) {
997     Action *Act = SingleActions[i];
998 
999     // Make sure we can lipo this kind of output. If not (and it is an actual
1000     // output) then we disallow, since we can't create an output file with the
1001     // right name without overwriting it. We could remove this oddity by just
1002     // changing the output names to include the arch, which would also fix
1003     // -save-temps. Compatibility wins for now.
1004 
1005     if (Archs.size() > 1 && !types::canLipoType(Act->getType()))
1006       Diag(clang::diag::err_drv_invalid_output_with_multiple_archs)
1007           << types::getTypeName(Act->getType());
1008 
1009     ActionList Inputs;
1010     for (unsigned i = 0, e = Archs.size(); i != e; ++i) {
1011       Inputs.push_back(
1012           new BindArchAction(std::unique_ptr<Action>(Act), Archs[i]));
1013       if (i != 0)
1014         Inputs.back()->setOwnsInputs(false);
1015     }
1016 
1017     // Lipo if necessary, we do it this way because we need to set the arch flag
1018     // so that -Xarch_ gets overwritten.
1019     if (Inputs.size() == 1 || Act->getType() == types::TY_Nothing)
1020       Actions.append(Inputs.begin(), Inputs.end());
1021     else
1022       Actions.push_back(new LipoJobAction(Inputs, Act->getType()));
1023 
1024     // Handle debug info queries.
1025     Arg *A = Args.getLastArg(options::OPT_g_Group);
1026     if (A && !A->getOption().matches(options::OPT_g0) &&
1027         !A->getOption().matches(options::OPT_gstabs) &&
1028         ContainsCompileOrAssembleAction(Actions.back())) {
1029 
1030       // Add a 'dsymutil' step if necessary, when debug info is enabled and we
1031       // have a compile input. We need to run 'dsymutil' ourselves in such cases
1032       // because the debug info will refer to a temporary object file which
1033       // will be removed at the end of the compilation process.
1034       if (Act->getType() == types::TY_Image) {
1035         ActionList Inputs;
1036         Inputs.push_back(Actions.back());
1037         Actions.pop_back();
1038         Actions.push_back(new DsymutilJobAction(Inputs, types::TY_dSYM));
1039       }
1040 
1041       // Verify the debug info output.
1042       if (Args.hasArg(options::OPT_verify_debug_info)) {
1043         std::unique_ptr<Action> VerifyInput(Actions.back());
1044         Actions.pop_back();
1045         Actions.push_back(new VerifyDebugInfoJobAction(std::move(VerifyInput),
1046                                                        types::TY_Nothing));
1047       }
1048     }
1049   }
1050 }
1051 
1052 /// \brief Check that the file referenced by Value exists. If it doesn't,
1053 /// issue a diagnostic and return false.
1054 static bool DiagnoseInputExistence(const Driver &D, const DerivedArgList &Args,
1055                                    StringRef Value) {
1056   if (!D.getCheckInputsExist())
1057     return true;
1058 
1059   // stdin always exists.
1060   if (Value == "-")
1061     return true;
1062 
1063   SmallString<64> Path(Value);
1064   if (Arg *WorkDir = Args.getLastArg(options::OPT_working_directory)) {
1065     if (!llvm::sys::path::is_absolute(Path)) {
1066       SmallString<64> Directory(WorkDir->getValue());
1067       llvm::sys::path::append(Directory, Value);
1068       Path.assign(Directory);
1069     }
1070   }
1071 
1072   if (llvm::sys::fs::exists(Twine(Path)))
1073     return true;
1074 
1075   if (D.IsCLMode() && !llvm::sys::path::is_absolute(Twine(Path)) &&
1076       llvm::sys::Process::FindInEnvPath("LIB", Value))
1077     return true;
1078 
1079   D.Diag(clang::diag::err_drv_no_such_file) << Path;
1080   return false;
1081 }
1082 
1083 // Construct a the list of inputs and their types.
1084 void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args,
1085                          InputList &Inputs) const {
1086   // Track the current user specified (-x) input. We also explicitly track the
1087   // argument used to set the type; we only want to claim the type when we
1088   // actually use it, so we warn about unused -x arguments.
1089   types::ID InputType = types::TY_Nothing;
1090   Arg *InputTypeArg = nullptr;
1091 
1092   // The last /TC or /TP option sets the input type to C or C++ globally.
1093   if (Arg *TCTP = Args.getLastArgNoClaim(options::OPT__SLASH_TC,
1094                                          options::OPT__SLASH_TP)) {
1095     InputTypeArg = TCTP;
1096     InputType = TCTP->getOption().matches(options::OPT__SLASH_TC)
1097                     ? types::TY_C
1098                     : types::TY_CXX;
1099 
1100     arg_iterator it =
1101         Args.filtered_begin(options::OPT__SLASH_TC, options::OPT__SLASH_TP);
1102     const arg_iterator ie = Args.filtered_end();
1103     Arg *Previous = *it++;
1104     bool ShowNote = false;
1105     while (it != ie) {
1106       Diag(clang::diag::warn_drv_overriding_flag_option)
1107           << Previous->getSpelling() << (*it)->getSpelling();
1108       Previous = *it++;
1109       ShowNote = true;
1110     }
1111     if (ShowNote)
1112       Diag(clang::diag::note_drv_t_option_is_global);
1113 
1114     // No driver mode exposes -x and /TC or /TP; we don't support mixing them.
1115     assert(!Args.hasArg(options::OPT_x) && "-x and /TC or /TP is not allowed");
1116   }
1117 
1118   for (Arg *A : Args) {
1119     if (A->getOption().getKind() == Option::InputClass) {
1120       const char *Value = A->getValue();
1121       types::ID Ty = types::TY_INVALID;
1122 
1123       // Infer the input type if necessary.
1124       if (InputType == types::TY_Nothing) {
1125         // If there was an explicit arg for this, claim it.
1126         if (InputTypeArg)
1127           InputTypeArg->claim();
1128 
1129         // stdin must be handled specially.
1130         if (memcmp(Value, "-", 2) == 0) {
1131           // If running with -E, treat as a C input (this changes the builtin
1132           // macros, for example). This may be overridden by -ObjC below.
1133           //
1134           // Otherwise emit an error but still use a valid type to avoid
1135           // spurious errors (e.g., no inputs).
1136           if (!Args.hasArgNoClaim(options::OPT_E) && !CCCIsCPP())
1137             Diag(IsCLMode() ? clang::diag::err_drv_unknown_stdin_type_clang_cl
1138                             : clang::diag::err_drv_unknown_stdin_type);
1139           Ty = types::TY_C;
1140         } else {
1141           // Otherwise lookup by extension.
1142           // Fallback is C if invoked as C preprocessor or Object otherwise.
1143           // We use a host hook here because Darwin at least has its own
1144           // idea of what .s is.
1145           if (const char *Ext = strrchr(Value, '.'))
1146             Ty = TC.LookupTypeForExtension(Ext + 1);
1147 
1148           if (Ty == types::TY_INVALID) {
1149             if (CCCIsCPP())
1150               Ty = types::TY_C;
1151             else
1152               Ty = types::TY_Object;
1153           }
1154 
1155           // If the driver is invoked as C++ compiler (like clang++ or c++) it
1156           // should autodetect some input files as C++ for g++ compatibility.
1157           if (CCCIsCXX()) {
1158             types::ID OldTy = Ty;
1159             Ty = types::lookupCXXTypeForCType(Ty);
1160 
1161             if (Ty != OldTy)
1162               Diag(clang::diag::warn_drv_treating_input_as_cxx)
1163                   << getTypeName(OldTy) << getTypeName(Ty);
1164           }
1165         }
1166 
1167         // -ObjC and -ObjC++ override the default language, but only for "source
1168         // files". We just treat everything that isn't a linker input as a
1169         // source file.
1170         //
1171         // FIXME: Clean this up if we move the phase sequence into the type.
1172         if (Ty != types::TY_Object) {
1173           if (Args.hasArg(options::OPT_ObjC))
1174             Ty = types::TY_ObjC;
1175           else if (Args.hasArg(options::OPT_ObjCXX))
1176             Ty = types::TY_ObjCXX;
1177         }
1178       } else {
1179         assert(InputTypeArg && "InputType set w/o InputTypeArg");
1180         if (!InputTypeArg->getOption().matches(options::OPT_x)) {
1181           // If emulating cl.exe, make sure that /TC and /TP don't affect input
1182           // object files.
1183           const char *Ext = strrchr(Value, '.');
1184           if (Ext && TC.LookupTypeForExtension(Ext + 1) == types::TY_Object)
1185             Ty = types::TY_Object;
1186         }
1187         if (Ty == types::TY_INVALID) {
1188           Ty = InputType;
1189           InputTypeArg->claim();
1190         }
1191       }
1192 
1193       if (DiagnoseInputExistence(*this, Args, Value))
1194         Inputs.push_back(std::make_pair(Ty, A));
1195 
1196     } else if (A->getOption().matches(options::OPT__SLASH_Tc)) {
1197       StringRef Value = A->getValue();
1198       if (DiagnoseInputExistence(*this, Args, Value)) {
1199         Arg *InputArg = MakeInputArg(Args, Opts, A->getValue());
1200         Inputs.push_back(std::make_pair(types::TY_C, InputArg));
1201       }
1202       A->claim();
1203     } else if (A->getOption().matches(options::OPT__SLASH_Tp)) {
1204       StringRef Value = A->getValue();
1205       if (DiagnoseInputExistence(*this, Args, Value)) {
1206         Arg *InputArg = MakeInputArg(Args, Opts, A->getValue());
1207         Inputs.push_back(std::make_pair(types::TY_CXX, InputArg));
1208       }
1209       A->claim();
1210     } else if (A->getOption().hasFlag(options::LinkerInput)) {
1211       // Just treat as object type, we could make a special type for this if
1212       // necessary.
1213       Inputs.push_back(std::make_pair(types::TY_Object, A));
1214 
1215     } else if (A->getOption().matches(options::OPT_x)) {
1216       InputTypeArg = A;
1217       InputType = types::lookupTypeForTypeSpecifier(A->getValue());
1218       A->claim();
1219 
1220       // Follow gcc behavior and treat as linker input for invalid -x
1221       // options. Its not clear why we shouldn't just revert to unknown; but
1222       // this isn't very important, we might as well be bug compatible.
1223       if (!InputType) {
1224         Diag(clang::diag::err_drv_unknown_language) << A->getValue();
1225         InputType = types::TY_Object;
1226       }
1227     }
1228   }
1229   if (CCCIsCPP() && Inputs.empty()) {
1230     // If called as standalone preprocessor, stdin is processed
1231     // if no other input is present.
1232     Arg *A = MakeInputArg(Args, Opts, "-");
1233     Inputs.push_back(std::make_pair(types::TY_C, A));
1234   }
1235 }
1236 
1237 // For each unique --cuda-gpu-arch= argument creates a TY_CUDA_DEVICE
1238 // input action and then wraps each in CudaDeviceAction paired with
1239 // appropriate GPU arch name. In case of partial (i.e preprocessing
1240 // only) or device-only compilation, each device action is added to /p
1241 // Actions and /p Current is released. Otherwise the function creates
1242 // and returns a new CudaHostAction which wraps /p Current and device
1243 // side actions.
1244 static std::unique_ptr<Action>
1245 buildCudaActions(const Driver &D, const ToolChain &TC, DerivedArgList &Args,
1246                  const Arg *InputArg, std::unique_ptr<Action> HostAction,
1247                  ActionList &Actions) {
1248 
1249   // Collect all cuda_gpu_arch parameters, removing duplicates.
1250   SmallVector<const char *, 4> GpuArchList;
1251   llvm::StringSet<> GpuArchNames;
1252   for (Arg *A : Args) {
1253     if (A->getOption().matches(options::OPT_cuda_gpu_arch_EQ)) {
1254       A->claim();
1255       if (GpuArchNames.insert(A->getValue()).second)
1256         GpuArchList.push_back(A->getValue());
1257     }
1258   }
1259 
1260   // Default to sm_20 which is the lowest common denominator for supported GPUs.
1261   // sm_20 code should work correctly, if suboptimally, on all newer GPUs.
1262   if (GpuArchList.empty())
1263     GpuArchList.push_back("sm_20");
1264 
1265   // Replicate inputs for each GPU architecture.
1266   Driver::InputList CudaDeviceInputs;
1267   for (unsigned I = 0, E = GpuArchList.size(); I != E; ++I)
1268     CudaDeviceInputs.push_back(std::make_pair(types::TY_CUDA_DEVICE, InputArg));
1269 
1270   // Build actions for all device inputs.
1271   ActionList CudaDeviceActions;
1272   D.BuildActions(TC, Args, CudaDeviceInputs, CudaDeviceActions);
1273   assert(GpuArchList.size() == CudaDeviceActions.size() &&
1274          "Failed to create actions for all devices");
1275 
1276   // Check whether any of device actions stopped before they could generate PTX.
1277   bool PartialCompilation = false;
1278   for (unsigned I = 0, E = GpuArchList.size(); I != E; ++I) {
1279     if (CudaDeviceActions[I]->getKind() != Action::BackendJobClass) {
1280       PartialCompilation = true;
1281       break;
1282     }
1283   }
1284 
1285   // Figure out which NVPTX triple to use for device-side compilation based on
1286   // whether host is 64-bit.
1287   const char *DeviceTriple = TC.getTriple().isArch64Bit()
1288                                  ? "nvptx64-nvidia-cuda"
1289                                  : "nvptx-nvidia-cuda";
1290 
1291   // Figure out what to do with device actions -- pass them as inputs to the
1292   // host action or run each of them independently.
1293   bool DeviceOnlyCompilation = Args.hasArg(options::OPT_cuda_device_only);
1294   if (PartialCompilation || DeviceOnlyCompilation) {
1295     // In case of partial or device-only compilation results of device actions
1296     // are not consumed by the host action device actions have to be added to
1297     // top-level actions list with AtTopLevel=true and run independently.
1298 
1299     // -o is ambiguous if we have more than one top-level action.
1300     if (Args.hasArg(options::OPT_o) &&
1301         (!DeviceOnlyCompilation || GpuArchList.size() > 1)) {
1302       D.Diag(clang::diag::err_drv_output_argument_with_multiple_files);
1303       return nullptr;
1304     }
1305 
1306     for (unsigned I = 0, E = GpuArchList.size(); I != E; ++I)
1307       Actions.push_back(new CudaDeviceAction(
1308           std::unique_ptr<Action>(CudaDeviceActions[I]), GpuArchList[I],
1309           DeviceTriple, /* AtTopLevel */ true));
1310     // Kill host action in case of device-only compilation.
1311     if (DeviceOnlyCompilation)
1312       HostAction.reset(nullptr);
1313     return HostAction;
1314   }
1315 
1316   // Outputs of device actions during complete CUDA compilation get created
1317   // with AtTopLevel=false and become inputs for the host action.
1318   ActionList DeviceActions;
1319   for (unsigned I = 0, E = GpuArchList.size(); I != E; ++I)
1320     DeviceActions.push_back(new CudaDeviceAction(
1321         std::unique_ptr<Action>(CudaDeviceActions[I]), GpuArchList[I],
1322         DeviceTriple, /* AtTopLevel */ false));
1323   // Return a new host action that incorporates original host action and all
1324   // device actions.
1325   return std::unique_ptr<Action>(
1326       new CudaHostAction(std::move(HostAction), DeviceActions));
1327 }
1328 
1329 void Driver::BuildActions(const ToolChain &TC, DerivedArgList &Args,
1330                           const InputList &Inputs, ActionList &Actions) const {
1331   llvm::PrettyStackTraceString CrashInfo("Building compilation actions");
1332 
1333   if (!SuppressMissingInputWarning && Inputs.empty()) {
1334     Diag(clang::diag::err_drv_no_input_files);
1335     return;
1336   }
1337 
1338   Arg *FinalPhaseArg;
1339   phases::ID FinalPhase = getFinalPhase(Args, &FinalPhaseArg);
1340 
1341   if (FinalPhase == phases::Link && Args.hasArg(options::OPT_emit_llvm)) {
1342     Diag(clang::diag::err_drv_emit_llvm_link);
1343   }
1344 
1345   // Reject -Z* at the top level, these options should never have been exposed
1346   // by gcc.
1347   if (Arg *A = Args.getLastArg(options::OPT_Z_Joined))
1348     Diag(clang::diag::err_drv_use_of_Z_option) << A->getAsString(Args);
1349 
1350   // Diagnose misuse of /Fo.
1351   if (Arg *A = Args.getLastArg(options::OPT__SLASH_Fo)) {
1352     StringRef V = A->getValue();
1353     if (Inputs.size() > 1 && !V.empty() &&
1354         !llvm::sys::path::is_separator(V.back())) {
1355       // Check whether /Fo tries to name an output file for multiple inputs.
1356       Diag(clang::diag::err_drv_out_file_argument_with_multiple_sources)
1357           << A->getSpelling() << V;
1358       Args.eraseArg(options::OPT__SLASH_Fo);
1359     }
1360   }
1361 
1362   // Diagnose misuse of /Fa.
1363   if (Arg *A = Args.getLastArg(options::OPT__SLASH_Fa)) {
1364     StringRef V = A->getValue();
1365     if (Inputs.size() > 1 && !V.empty() &&
1366         !llvm::sys::path::is_separator(V.back())) {
1367       // Check whether /Fa tries to name an asm file for multiple inputs.
1368       Diag(clang::diag::err_drv_out_file_argument_with_multiple_sources)
1369           << A->getSpelling() << V;
1370       Args.eraseArg(options::OPT__SLASH_Fa);
1371     }
1372   }
1373 
1374   // Diagnose misuse of /o.
1375   if (Arg *A = Args.getLastArg(options::OPT__SLASH_o)) {
1376     if (A->getValue()[0] == '\0') {
1377       // It has to have a value.
1378       Diag(clang::diag::err_drv_missing_argument) << A->getSpelling() << 1;
1379       Args.eraseArg(options::OPT__SLASH_o);
1380     }
1381   }
1382 
1383   // Construct the actions to perform.
1384   ActionList LinkerInputs;
1385 
1386   llvm::SmallVector<phases::ID, phases::MaxNumberOfPhases> PL;
1387   for (auto &I : Inputs) {
1388     types::ID InputType = I.first;
1389     const Arg *InputArg = I.second;
1390 
1391     PL.clear();
1392     types::getCompilationPhases(InputType, PL);
1393 
1394     // If the first step comes after the final phase we are doing as part of
1395     // this compilation, warn the user about it.
1396     phases::ID InitialPhase = PL[0];
1397     if (InitialPhase > FinalPhase) {
1398       // Claim here to avoid the more general unused warning.
1399       InputArg->claim();
1400 
1401       // Suppress all unused style warnings with -Qunused-arguments
1402       if (Args.hasArg(options::OPT_Qunused_arguments))
1403         continue;
1404 
1405       // Special case when final phase determined by binary name, rather than
1406       // by a command-line argument with a corresponding Arg.
1407       if (CCCIsCPP())
1408         Diag(clang::diag::warn_drv_input_file_unused_by_cpp)
1409             << InputArg->getAsString(Args) << getPhaseName(InitialPhase);
1410       // Special case '-E' warning on a previously preprocessed file to make
1411       // more sense.
1412       else if (InitialPhase == phases::Compile &&
1413                FinalPhase == phases::Preprocess &&
1414                getPreprocessedType(InputType) == types::TY_INVALID)
1415         Diag(clang::diag::warn_drv_preprocessed_input_file_unused)
1416             << InputArg->getAsString(Args) << !!FinalPhaseArg
1417             << (FinalPhaseArg ? FinalPhaseArg->getOption().getName() : "");
1418       else
1419         Diag(clang::diag::warn_drv_input_file_unused)
1420             << InputArg->getAsString(Args) << getPhaseName(InitialPhase)
1421             << !!FinalPhaseArg
1422             << (FinalPhaseArg ? FinalPhaseArg->getOption().getName() : "");
1423       continue;
1424     }
1425 
1426     phases::ID CudaInjectionPhase;
1427     bool InjectCuda = (InputType == types::TY_CUDA &&
1428                        !Args.hasArg(options::OPT_cuda_host_only));
1429     CudaInjectionPhase = FinalPhase;
1430     for (auto &Phase : PL)
1431       if (Phase <= FinalPhase && Phase == phases::Compile) {
1432         CudaInjectionPhase = Phase;
1433         break;
1434       }
1435 
1436     // Build the pipeline for this file.
1437     std::unique_ptr<Action> Current(new InputAction(*InputArg, InputType));
1438     for (SmallVectorImpl<phases::ID>::iterator i = PL.begin(), e = PL.end();
1439          i != e; ++i) {
1440       phases::ID Phase = *i;
1441 
1442       // We are done if this step is past what the user requested.
1443       if (Phase > FinalPhase)
1444         break;
1445 
1446       // Queue linker inputs.
1447       if (Phase == phases::Link) {
1448         assert((i + 1) == e && "linking must be final compilation step.");
1449         LinkerInputs.push_back(Current.release());
1450         break;
1451       }
1452 
1453       // Some types skip the assembler phase (e.g., llvm-bc), but we can't
1454       // encode this in the steps because the intermediate type depends on
1455       // arguments. Just special case here.
1456       if (Phase == phases::Assemble && Current->getType() != types::TY_PP_Asm)
1457         continue;
1458 
1459       // Otherwise construct the appropriate action.
1460       Current = ConstructPhaseAction(TC, Args, Phase, std::move(Current));
1461 
1462       if (InjectCuda && Phase == CudaInjectionPhase) {
1463         Current = buildCudaActions(*this, TC, Args, InputArg,
1464                                    std::move(Current), Actions);
1465         if (!Current)
1466           break;
1467       }
1468 
1469       if (Current->getType() == types::TY_Nothing)
1470         break;
1471     }
1472 
1473     // If we ended with something, add to the output list.
1474     if (Current)
1475       Actions.push_back(Current.release());
1476   }
1477 
1478   // Add a link action if necessary.
1479   if (!LinkerInputs.empty())
1480     Actions.push_back(new LinkJobAction(LinkerInputs, types::TY_Image));
1481 
1482   // If we are linking, claim any options which are obviously only used for
1483   // compilation.
1484   if (FinalPhase == phases::Link && PL.size() == 1) {
1485     Args.ClaimAllArgs(options::OPT_CompileOnly_Group);
1486     Args.ClaimAllArgs(options::OPT_cl_compile_Group);
1487   }
1488 
1489   // Claim ignored clang-cl options.
1490   Args.ClaimAllArgs(options::OPT_cl_ignored_Group);
1491 
1492   // Claim --cuda-host-only arg which may be passed to non-CUDA
1493   // compilations and should not trigger warnings there.
1494   Args.ClaimAllArgs(options::OPT_cuda_host_only);
1495 }
1496 
1497 std::unique_ptr<Action>
1498 Driver::ConstructPhaseAction(const ToolChain &TC, const ArgList &Args,
1499                              phases::ID Phase,
1500                              std::unique_ptr<Action> Input) const {
1501   llvm::PrettyStackTraceString CrashInfo("Constructing phase actions");
1502   // Build the appropriate action.
1503   switch (Phase) {
1504   case phases::Link:
1505     llvm_unreachable("link action invalid here.");
1506   case phases::Preprocess: {
1507     types::ID OutputTy;
1508     // -{M, MM} alter the output type.
1509     if (Args.hasArg(options::OPT_M, options::OPT_MM)) {
1510       OutputTy = types::TY_Dependencies;
1511     } else {
1512       OutputTy = Input->getType();
1513       if (!Args.hasFlag(options::OPT_frewrite_includes,
1514                         options::OPT_fno_rewrite_includes, false) &&
1515           !CCGenDiagnostics)
1516         OutputTy = types::getPreprocessedType(OutputTy);
1517       assert(OutputTy != types::TY_INVALID &&
1518              "Cannot preprocess this input type!");
1519     }
1520     return llvm::make_unique<PreprocessJobAction>(std::move(Input), OutputTy);
1521   }
1522   case phases::Precompile: {
1523     types::ID OutputTy = types::TY_PCH;
1524     if (Args.hasArg(options::OPT_fsyntax_only)) {
1525       // Syntax checks should not emit a PCH file
1526       OutputTy = types::TY_Nothing;
1527     }
1528     return llvm::make_unique<PrecompileJobAction>(std::move(Input), OutputTy);
1529   }
1530   case phases::Compile: {
1531     if (Args.hasArg(options::OPT_fsyntax_only))
1532       return llvm::make_unique<CompileJobAction>(std::move(Input),
1533                                                  types::TY_Nothing);
1534     if (Args.hasArg(options::OPT_rewrite_objc))
1535       return llvm::make_unique<CompileJobAction>(std::move(Input),
1536                                                  types::TY_RewrittenObjC);
1537     if (Args.hasArg(options::OPT_rewrite_legacy_objc))
1538       return llvm::make_unique<CompileJobAction>(std::move(Input),
1539                                                  types::TY_RewrittenLegacyObjC);
1540     if (Args.hasArg(options::OPT__analyze, options::OPT__analyze_auto))
1541       return llvm::make_unique<AnalyzeJobAction>(std::move(Input),
1542                                                  types::TY_Plist);
1543     if (Args.hasArg(options::OPT__migrate))
1544       return llvm::make_unique<MigrateJobAction>(std::move(Input),
1545                                                  types::TY_Remap);
1546     if (Args.hasArg(options::OPT_emit_ast))
1547       return llvm::make_unique<CompileJobAction>(std::move(Input),
1548                                                  types::TY_AST);
1549     if (Args.hasArg(options::OPT_module_file_info))
1550       return llvm::make_unique<CompileJobAction>(std::move(Input),
1551                                                  types::TY_ModuleFile);
1552     if (Args.hasArg(options::OPT_verify_pch))
1553       return llvm::make_unique<VerifyPCHJobAction>(std::move(Input),
1554                                                    types::TY_Nothing);
1555     return llvm::make_unique<CompileJobAction>(std::move(Input),
1556                                                types::TY_LLVM_BC);
1557   }
1558   case phases::Backend: {
1559     if (IsUsingLTO(Args)) {
1560       types::ID Output =
1561           Args.hasArg(options::OPT_S) ? types::TY_LTO_IR : types::TY_LTO_BC;
1562       return llvm::make_unique<BackendJobAction>(std::move(Input), Output);
1563     }
1564     if (Args.hasArg(options::OPT_emit_llvm)) {
1565       types::ID Output =
1566           Args.hasArg(options::OPT_S) ? types::TY_LLVM_IR : types::TY_LLVM_BC;
1567       return llvm::make_unique<BackendJobAction>(std::move(Input), Output);
1568     }
1569     return llvm::make_unique<BackendJobAction>(std::move(Input),
1570                                                types::TY_PP_Asm);
1571   }
1572   case phases::Assemble:
1573     return llvm::make_unique<AssembleJobAction>(std::move(Input),
1574                                                 types::TY_Object);
1575   }
1576 
1577   llvm_unreachable("invalid phase in ConstructPhaseAction");
1578 }
1579 
1580 bool Driver::IsUsingLTO(const ArgList &Args) const {
1581   return Args.hasFlag(options::OPT_flto, options::OPT_fno_lto, false);
1582 }
1583 
1584 void Driver::BuildJobs(Compilation &C) const {
1585   llvm::PrettyStackTraceString CrashInfo("Building compilation jobs");
1586 
1587   Arg *FinalOutput = C.getArgs().getLastArg(options::OPT_o);
1588 
1589   // It is an error to provide a -o option if we are making multiple output
1590   // files.
1591   if (FinalOutput) {
1592     unsigned NumOutputs = 0;
1593     for (const Action *A : C.getActions())
1594       if (A->getType() != types::TY_Nothing)
1595         ++NumOutputs;
1596 
1597     if (NumOutputs > 1) {
1598       Diag(clang::diag::err_drv_output_argument_with_multiple_files);
1599       FinalOutput = nullptr;
1600     }
1601   }
1602 
1603   // Collect the list of architectures.
1604   llvm::StringSet<> ArchNames;
1605   if (C.getDefaultToolChain().getTriple().isOSBinFormatMachO())
1606     for (const Arg *A : C.getArgs())
1607       if (A->getOption().matches(options::OPT_arch))
1608         ArchNames.insert(A->getValue());
1609 
1610   for (Action *A : C.getActions()) {
1611     // If we are linking an image for multiple archs then the linker wants
1612     // -arch_multiple and -final_output <final image name>. Unfortunately, this
1613     // doesn't fit in cleanly because we have to pass this information down.
1614     //
1615     // FIXME: This is a hack; find a cleaner way to integrate this into the
1616     // process.
1617     const char *LinkingOutput = nullptr;
1618     if (isa<LipoJobAction>(A)) {
1619       if (FinalOutput)
1620         LinkingOutput = FinalOutput->getValue();
1621       else
1622         LinkingOutput = getDefaultImageName();
1623     }
1624 
1625     InputInfo II;
1626     BuildJobsForAction(C, A, &C.getDefaultToolChain(),
1627                        /*BoundArch*/ nullptr,
1628                        /*AtTopLevel*/ true,
1629                        /*MultipleArchs*/ ArchNames.size() > 1,
1630                        /*LinkingOutput*/ LinkingOutput, II);
1631   }
1632 
1633   // If the user passed -Qunused-arguments or there were errors, don't warn
1634   // about any unused arguments.
1635   if (Diags.hasErrorOccurred() ||
1636       C.getArgs().hasArg(options::OPT_Qunused_arguments))
1637     return;
1638 
1639   // Claim -### here.
1640   (void)C.getArgs().hasArg(options::OPT__HASH_HASH_HASH);
1641 
1642   // Claim --driver-mode, it was handled earlier.
1643   (void)C.getArgs().hasArg(options::OPT_driver_mode);
1644 
1645   for (Arg *A : C.getArgs()) {
1646     // FIXME: It would be nice to be able to send the argument to the
1647     // DiagnosticsEngine, so that extra values, position, and so on could be
1648     // printed.
1649     if (!A->isClaimed()) {
1650       if (A->getOption().hasFlag(options::NoArgumentUnused))
1651         continue;
1652 
1653       // Suppress the warning automatically if this is just a flag, and it is an
1654       // instance of an argument we already claimed.
1655       const Option &Opt = A->getOption();
1656       if (Opt.getKind() == Option::FlagClass) {
1657         bool DuplicateClaimed = false;
1658 
1659         for (const Arg *AA : C.getArgs().filtered(&Opt)) {
1660           if (AA->isClaimed()) {
1661             DuplicateClaimed = true;
1662             break;
1663           }
1664         }
1665 
1666         if (DuplicateClaimed)
1667           continue;
1668       }
1669 
1670       Diag(clang::diag::warn_drv_unused_argument)
1671           << A->getAsString(C.getArgs());
1672     }
1673   }
1674 }
1675 
1676 // Returns a Tool for a given JobAction.  In case the action and its
1677 // predecessors can be combined, updates Inputs with the inputs of the
1678 // first combined action. If one of the collapsed actions is a
1679 // CudaHostAction, updates CollapsedCHA with the pointer to it so the
1680 // caller can deal with extra handling such action requires.
1681 static const Tool *selectToolForJob(Compilation &C, bool SaveTemps,
1682                                     const ToolChain *TC, const JobAction *JA,
1683                                     const ActionList *&Inputs,
1684                                     const CudaHostAction *&CollapsedCHA) {
1685   const Tool *ToolForJob = nullptr;
1686   CollapsedCHA = nullptr;
1687 
1688   // See if we should look for a compiler with an integrated assembler. We match
1689   // bottom up, so what we are actually looking for is an assembler job with a
1690   // compiler input.
1691 
1692   if (TC->useIntegratedAs() && !SaveTemps &&
1693       !C.getArgs().hasArg(options::OPT_via_file_asm) &&
1694       !C.getArgs().hasArg(options::OPT__SLASH_FA) &&
1695       !C.getArgs().hasArg(options::OPT__SLASH_Fa) &&
1696       isa<AssembleJobAction>(JA) && Inputs->size() == 1 &&
1697       isa<BackendJobAction>(*Inputs->begin())) {
1698     // A BackendJob is always preceded by a CompileJob, and without
1699     // -save-temps they will always get combined together, so instead of
1700     // checking the backend tool, check if the tool for the CompileJob
1701     // has an integrated assembler.
1702     const ActionList *BackendInputs = &(*Inputs)[0]->getInputs();
1703     // Compile job may be wrapped in CudaHostAction, extract it if
1704     // that's the case and update CollapsedCHA if we combine phases.
1705     CudaHostAction *CHA = dyn_cast<CudaHostAction>(*BackendInputs->begin());
1706     JobAction *CompileJA =
1707         cast<CompileJobAction>(CHA ? *CHA->begin() : *BackendInputs->begin());
1708     assert(CompileJA && "Backend job is not preceeded by compile job.");
1709     const Tool *Compiler = TC->SelectTool(*CompileJA);
1710     if (!Compiler)
1711       return nullptr;
1712     if (Compiler->hasIntegratedAssembler()) {
1713       Inputs = &CompileJA->getInputs();
1714       ToolForJob = Compiler;
1715       CollapsedCHA = CHA;
1716     }
1717   }
1718 
1719   // A backend job should always be combined with the preceding compile job
1720   // unless OPT_save_temps is enabled and the compiler is capable of emitting
1721   // LLVM IR as an intermediate output.
1722   if (isa<BackendJobAction>(JA)) {
1723     // Check if the compiler supports emitting LLVM IR.
1724     assert(Inputs->size() == 1);
1725     // Compile job may be wrapped in CudaHostAction, extract it if
1726     // that's the case and update CollapsedCHA if we combine phases.
1727     CudaHostAction *CHA = dyn_cast<CudaHostAction>(*Inputs->begin());
1728     JobAction *CompileJA =
1729         cast<CompileJobAction>(CHA ? *CHA->begin() : *Inputs->begin());
1730     assert(CompileJA && "Backend job is not preceeded by compile job.");
1731     const Tool *Compiler = TC->SelectTool(*CompileJA);
1732     if (!Compiler)
1733       return nullptr;
1734     if (!Compiler->canEmitIR() || !SaveTemps) {
1735       Inputs = &CompileJA->getInputs();
1736       ToolForJob = Compiler;
1737       CollapsedCHA = CHA;
1738     }
1739   }
1740 
1741   // Otherwise use the tool for the current job.
1742   if (!ToolForJob)
1743     ToolForJob = TC->SelectTool(*JA);
1744 
1745   // See if we should use an integrated preprocessor. We do so when we have
1746   // exactly one input, since this is the only use case we care about
1747   // (irrelevant since we don't support combine yet).
1748   if (Inputs->size() == 1 && isa<PreprocessJobAction>(*Inputs->begin()) &&
1749       !C.getArgs().hasArg(options::OPT_no_integrated_cpp) &&
1750       !C.getArgs().hasArg(options::OPT_traditional_cpp) && !SaveTemps &&
1751       !C.getArgs().hasArg(options::OPT_rewrite_objc) &&
1752       ToolForJob->hasIntegratedCPP())
1753     Inputs = &(*Inputs)[0]->getInputs();
1754 
1755   return ToolForJob;
1756 }
1757 
1758 void Driver::BuildJobsForAction(Compilation &C, const Action *A,
1759                                 const ToolChain *TC, const char *BoundArch,
1760                                 bool AtTopLevel, bool MultipleArchs,
1761                                 const char *LinkingOutput,
1762                                 InputInfo &Result) const {
1763   llvm::PrettyStackTraceString CrashInfo("Building compilation jobs");
1764 
1765   InputInfoList CudaDeviceInputInfos;
1766   if (const CudaHostAction *CHA = dyn_cast<CudaHostAction>(A)) {
1767     InputInfo II;
1768     // Append outputs of device jobs to the input list.
1769     for (const Action *DA : CHA->getDeviceActions()) {
1770       BuildJobsForAction(C, DA, TC, "", AtTopLevel,
1771                          /*MultipleArchs*/ false, LinkingOutput, II);
1772       CudaDeviceInputInfos.push_back(II);
1773     }
1774     // Override current action with a real host compile action and continue
1775     // processing it.
1776     A = *CHA->begin();
1777   }
1778 
1779   if (const InputAction *IA = dyn_cast<InputAction>(A)) {
1780     // FIXME: It would be nice to not claim this here; maybe the old scheme of
1781     // just using Args was better?
1782     const Arg &Input = IA->getInputArg();
1783     Input.claim();
1784     if (Input.getOption().matches(options::OPT_INPUT)) {
1785       const char *Name = Input.getValue();
1786       Result = InputInfo(Name, A->getType(), Name);
1787     } else {
1788       Result = InputInfo(&Input, A->getType(), "");
1789     }
1790     return;
1791   }
1792 
1793   if (const BindArchAction *BAA = dyn_cast<BindArchAction>(A)) {
1794     const ToolChain *TC;
1795     const char *ArchName = BAA->getArchName();
1796 
1797     if (ArchName)
1798       TC = &getToolChain(
1799           C.getArgs(),
1800           computeTargetTriple(DefaultTargetTriple, C.getArgs(), ArchName));
1801     else
1802       TC = &C.getDefaultToolChain();
1803 
1804     BuildJobsForAction(C, *BAA->begin(), TC, ArchName, AtTopLevel,
1805                        MultipleArchs, LinkingOutput, Result);
1806     return;
1807   }
1808 
1809   if (const CudaDeviceAction *CDA = dyn_cast<CudaDeviceAction>(A)) {
1810     BuildJobsForAction(
1811         C, *CDA->begin(),
1812         &getToolChain(C.getArgs(), llvm::Triple(CDA->getDeviceTriple())),
1813         CDA->getGpuArchName(), CDA->isAtTopLevel(),
1814         /*MultipleArchs*/ true, LinkingOutput, Result);
1815     return;
1816   }
1817 
1818   const ActionList *Inputs = &A->getInputs();
1819 
1820   const JobAction *JA = cast<JobAction>(A);
1821   const CudaHostAction *CollapsedCHA = nullptr;
1822   const Tool *T =
1823       selectToolForJob(C, isSaveTempsEnabled(), TC, JA, Inputs, CollapsedCHA);
1824   if (!T)
1825     return;
1826 
1827   // If we've collapsed action list that contained CudaHostAction we
1828   // need to build jobs for device-side inputs it may have held.
1829   if (CollapsedCHA) {
1830     InputInfo II;
1831     for (const Action *DA : CollapsedCHA->getDeviceActions()) {
1832       BuildJobsForAction(C, DA, TC, "", AtTopLevel,
1833                          /*MultipleArchs*/ false, LinkingOutput, II);
1834       CudaDeviceInputInfos.push_back(II);
1835     }
1836   }
1837 
1838   // Only use pipes when there is exactly one input.
1839   InputInfoList InputInfos;
1840   for (const Action *Input : *Inputs) {
1841     // Treat dsymutil and verify sub-jobs as being at the top-level too, they
1842     // shouldn't get temporary output names.
1843     // FIXME: Clean this up.
1844     bool SubJobAtTopLevel = false;
1845     if (AtTopLevel && (isa<DsymutilJobAction>(A) || isa<VerifyJobAction>(A)))
1846       SubJobAtTopLevel = true;
1847 
1848     InputInfo II;
1849     BuildJobsForAction(C, Input, TC, BoundArch, SubJobAtTopLevel, MultipleArchs,
1850                        LinkingOutput, II);
1851     InputInfos.push_back(II);
1852   }
1853 
1854   // Always use the first input as the base input.
1855   const char *BaseInput = InputInfos[0].getBaseInput();
1856 
1857   // ... except dsymutil actions, which use their actual input as the base
1858   // input.
1859   if (JA->getType() == types::TY_dSYM)
1860     BaseInput = InputInfos[0].getFilename();
1861 
1862   // Append outputs of cuda device jobs to the input list
1863   if (CudaDeviceInputInfos.size())
1864     InputInfos.append(CudaDeviceInputInfos.begin(), CudaDeviceInputInfos.end());
1865 
1866   // Determine the place to write output to, if any.
1867   if (JA->getType() == types::TY_Nothing)
1868     Result = InputInfo(A->getType(), BaseInput);
1869   else
1870     Result = InputInfo(GetNamedOutputPath(C, *JA, BaseInput, BoundArch,
1871                                           AtTopLevel, MultipleArchs),
1872                        A->getType(), BaseInput);
1873 
1874   if (CCCPrintBindings && !CCGenDiagnostics) {
1875     llvm::errs() << "# \"" << T->getToolChain().getTripleString() << '"'
1876                  << " - \"" << T->getName() << "\", inputs: [";
1877     for (unsigned i = 0, e = InputInfos.size(); i != e; ++i) {
1878       llvm::errs() << InputInfos[i].getAsString();
1879       if (i + 1 != e)
1880         llvm::errs() << ", ";
1881     }
1882     llvm::errs() << "], output: " << Result.getAsString() << "\n";
1883   } else {
1884     T->ConstructJob(C, *JA, Result, InputInfos,
1885                     C.getArgsForToolChain(TC, BoundArch), LinkingOutput);
1886   }
1887 }
1888 
1889 const char *Driver::getDefaultImageName() const {
1890   llvm::Triple Target(llvm::Triple::normalize(DefaultTargetTriple));
1891   return Target.isOSWindows() ? "a.exe" : "a.out";
1892 }
1893 
1894 /// \brief Create output filename based on ArgValue, which could either be a
1895 /// full filename, filename without extension, or a directory. If ArgValue
1896 /// does not provide a filename, then use BaseName, and use the extension
1897 /// suitable for FileType.
1898 static const char *MakeCLOutputFilename(const ArgList &Args, StringRef ArgValue,
1899                                         StringRef BaseName,
1900                                         types::ID FileType) {
1901   SmallString<128> Filename = ArgValue;
1902 
1903   if (ArgValue.empty()) {
1904     // If the argument is empty, output to BaseName in the current dir.
1905     Filename = BaseName;
1906   } else if (llvm::sys::path::is_separator(Filename.back())) {
1907     // If the argument is a directory, output to BaseName in that dir.
1908     llvm::sys::path::append(Filename, BaseName);
1909   }
1910 
1911   if (!llvm::sys::path::has_extension(ArgValue)) {
1912     // If the argument didn't provide an extension, then set it.
1913     const char *Extension = types::getTypeTempSuffix(FileType, true);
1914 
1915     if (FileType == types::TY_Image &&
1916         Args.hasArg(options::OPT__SLASH_LD, options::OPT__SLASH_LDd)) {
1917       // The output file is a dll.
1918       Extension = "dll";
1919     }
1920 
1921     llvm::sys::path::replace_extension(Filename, Extension);
1922   }
1923 
1924   return Args.MakeArgString(Filename.c_str());
1925 }
1926 
1927 const char *Driver::GetNamedOutputPath(Compilation &C, const JobAction &JA,
1928                                        const char *BaseInput,
1929                                        const char *BoundArch, bool AtTopLevel,
1930                                        bool MultipleArchs) const {
1931   llvm::PrettyStackTraceString CrashInfo("Computing output path");
1932   // Output to a user requested destination?
1933   if (AtTopLevel && !isa<DsymutilJobAction>(JA) && !isa<VerifyJobAction>(JA)) {
1934     if (Arg *FinalOutput = C.getArgs().getLastArg(options::OPT_o))
1935       return C.addResultFile(FinalOutput->getValue(), &JA);
1936   }
1937 
1938   // For /P, preprocess to file named after BaseInput.
1939   if (C.getArgs().hasArg(options::OPT__SLASH_P)) {
1940     assert(AtTopLevel && isa<PreprocessJobAction>(JA));
1941     StringRef BaseName = llvm::sys::path::filename(BaseInput);
1942     StringRef NameArg;
1943     if (Arg *A = C.getArgs().getLastArg(options::OPT__SLASH_Fi))
1944       NameArg = A->getValue();
1945     return C.addResultFile(
1946         MakeCLOutputFilename(C.getArgs(), NameArg, BaseName, types::TY_PP_C),
1947         &JA);
1948   }
1949 
1950   // Default to writing to stdout?
1951   if (AtTopLevel && !CCGenDiagnostics &&
1952       (isa<PreprocessJobAction>(JA) || JA.getType() == types::TY_ModuleFile))
1953     return "-";
1954 
1955   // Is this the assembly listing for /FA?
1956   if (JA.getType() == types::TY_PP_Asm &&
1957       (C.getArgs().hasArg(options::OPT__SLASH_FA) ||
1958        C.getArgs().hasArg(options::OPT__SLASH_Fa))) {
1959     // Use /Fa and the input filename to determine the asm file name.
1960     StringRef BaseName = llvm::sys::path::filename(BaseInput);
1961     StringRef FaValue = C.getArgs().getLastArgValue(options::OPT__SLASH_Fa);
1962     return C.addResultFile(
1963         MakeCLOutputFilename(C.getArgs(), FaValue, BaseName, JA.getType()),
1964         &JA);
1965   }
1966 
1967   // Output to a temporary file?
1968   if ((!AtTopLevel && !isSaveTempsEnabled() &&
1969        !C.getArgs().hasArg(options::OPT__SLASH_Fo)) ||
1970       CCGenDiagnostics) {
1971     StringRef Name = llvm::sys::path::filename(BaseInput);
1972     std::pair<StringRef, StringRef> Split = Name.split('.');
1973     std::string TmpName = GetTemporaryPath(
1974         Split.first, types::getTypeTempSuffix(JA.getType(), IsCLMode()));
1975     return C.addTempFile(C.getArgs().MakeArgString(TmpName.c_str()));
1976   }
1977 
1978   SmallString<128> BasePath(BaseInput);
1979   StringRef BaseName;
1980 
1981   // Dsymutil actions should use the full path.
1982   if (isa<DsymutilJobAction>(JA) || isa<VerifyJobAction>(JA))
1983     BaseName = BasePath;
1984   else
1985     BaseName = llvm::sys::path::filename(BasePath);
1986 
1987   // Determine what the derived output name should be.
1988   const char *NamedOutput;
1989 
1990   if (JA.getType() == types::TY_Object &&
1991       C.getArgs().hasArg(options::OPT__SLASH_Fo, options::OPT__SLASH_o)) {
1992     // The /Fo or /o flag decides the object filename.
1993     StringRef Val =
1994         C.getArgs()
1995             .getLastArg(options::OPT__SLASH_Fo, options::OPT__SLASH_o)
1996             ->getValue();
1997     NamedOutput =
1998         MakeCLOutputFilename(C.getArgs(), Val, BaseName, types::TY_Object);
1999   } else if (JA.getType() == types::TY_Image &&
2000              C.getArgs().hasArg(options::OPT__SLASH_Fe,
2001                                 options::OPT__SLASH_o)) {
2002     // The /Fe or /o flag names the linked file.
2003     StringRef Val =
2004         C.getArgs()
2005             .getLastArg(options::OPT__SLASH_Fe, options::OPT__SLASH_o)
2006             ->getValue();
2007     NamedOutput =
2008         MakeCLOutputFilename(C.getArgs(), Val, BaseName, types::TY_Image);
2009   } else if (JA.getType() == types::TY_Image) {
2010     if (IsCLMode()) {
2011       // clang-cl uses BaseName for the executable name.
2012       NamedOutput =
2013           MakeCLOutputFilename(C.getArgs(), "", BaseName, types::TY_Image);
2014     } else if (MultipleArchs && BoundArch) {
2015       SmallString<128> Output(getDefaultImageName());
2016       Output += "-";
2017       Output.append(BoundArch);
2018       NamedOutput = C.getArgs().MakeArgString(Output.c_str());
2019     } else
2020       NamedOutput = getDefaultImageName();
2021   } else {
2022     const char *Suffix = types::getTypeTempSuffix(JA.getType(), IsCLMode());
2023     assert(Suffix && "All types used for output should have a suffix.");
2024 
2025     std::string::size_type End = std::string::npos;
2026     if (!types::appendSuffixForType(JA.getType()))
2027       End = BaseName.rfind('.');
2028     SmallString<128> Suffixed(BaseName.substr(0, End));
2029     if (MultipleArchs && BoundArch) {
2030       Suffixed += "-";
2031       Suffixed.append(BoundArch);
2032     }
2033     // When using both -save-temps and -emit-llvm, use a ".tmp.bc" suffix for
2034     // the unoptimized bitcode so that it does not get overwritten by the ".bc"
2035     // optimized bitcode output.
2036     if (!AtTopLevel && C.getArgs().hasArg(options::OPT_emit_llvm) &&
2037         JA.getType() == types::TY_LLVM_BC)
2038       Suffixed += ".tmp";
2039     Suffixed += '.';
2040     Suffixed += Suffix;
2041     NamedOutput = C.getArgs().MakeArgString(Suffixed.c_str());
2042   }
2043 
2044   // Prepend object file path if -save-temps=obj
2045   if (!AtTopLevel && isSaveTempsObj() && C.getArgs().hasArg(options::OPT_o) &&
2046       JA.getType() != types::TY_PCH) {
2047     Arg *FinalOutput = C.getArgs().getLastArg(options::OPT_o);
2048     SmallString<128> TempPath(FinalOutput->getValue());
2049     llvm::sys::path::remove_filename(TempPath);
2050     StringRef OutputFileName = llvm::sys::path::filename(NamedOutput);
2051     llvm::sys::path::append(TempPath, OutputFileName);
2052     NamedOutput = C.getArgs().MakeArgString(TempPath.c_str());
2053   }
2054 
2055   // If we're saving temps and the temp file conflicts with the input file,
2056   // then avoid overwriting input file.
2057   if (!AtTopLevel && isSaveTempsEnabled() && NamedOutput == BaseName) {
2058     bool SameFile = false;
2059     SmallString<256> Result;
2060     llvm::sys::fs::current_path(Result);
2061     llvm::sys::path::append(Result, BaseName);
2062     llvm::sys::fs::equivalent(BaseInput, Result.c_str(), SameFile);
2063     // Must share the same path to conflict.
2064     if (SameFile) {
2065       StringRef Name = llvm::sys::path::filename(BaseInput);
2066       std::pair<StringRef, StringRef> Split = Name.split('.');
2067       std::string TmpName = GetTemporaryPath(
2068           Split.first, types::getTypeTempSuffix(JA.getType(), IsCLMode()));
2069       return C.addTempFile(C.getArgs().MakeArgString(TmpName.c_str()));
2070     }
2071   }
2072 
2073   // As an annoying special case, PCH generation doesn't strip the pathname.
2074   if (JA.getType() == types::TY_PCH) {
2075     llvm::sys::path::remove_filename(BasePath);
2076     if (BasePath.empty())
2077       BasePath = NamedOutput;
2078     else
2079       llvm::sys::path::append(BasePath, NamedOutput);
2080     return C.addResultFile(C.getArgs().MakeArgString(BasePath.c_str()), &JA);
2081   } else {
2082     return C.addResultFile(NamedOutput, &JA);
2083   }
2084 }
2085 
2086 std::string Driver::GetFilePath(const char *Name, const ToolChain &TC) const {
2087   // Respect a limited subset of the '-Bprefix' functionality in GCC by
2088   // attempting to use this prefix when looking for file paths.
2089   for (const std::string &Dir : PrefixDirs) {
2090     if (Dir.empty())
2091       continue;
2092     SmallString<128> P(Dir[0] == '=' ? SysRoot + Dir.substr(1) : Dir);
2093     llvm::sys::path::append(P, Name);
2094     if (llvm::sys::fs::exists(Twine(P)))
2095       return P.str();
2096   }
2097 
2098   SmallString<128> P(ResourceDir);
2099   llvm::sys::path::append(P, Name);
2100   if (llvm::sys::fs::exists(Twine(P)))
2101     return P.str();
2102 
2103   for (const std::string &Dir : TC.getFilePaths()) {
2104     if (Dir.empty())
2105       continue;
2106     SmallString<128> P(Dir[0] == '=' ? SysRoot + Dir.substr(1) : Dir);
2107     llvm::sys::path::append(P, Name);
2108     if (llvm::sys::fs::exists(Twine(P)))
2109       return P.str();
2110   }
2111 
2112   return Name;
2113 }
2114 
2115 void Driver::generatePrefixedToolNames(
2116     const char *Tool, const ToolChain &TC,
2117     SmallVectorImpl<std::string> &Names) const {
2118   // FIXME: Needs a better variable than DefaultTargetTriple
2119   Names.emplace_back(DefaultTargetTriple + "-" + Tool);
2120   Names.emplace_back(Tool);
2121 }
2122 
2123 static bool ScanDirForExecutable(SmallString<128> &Dir,
2124                                  ArrayRef<std::string> Names) {
2125   for (const auto &Name : Names) {
2126     llvm::sys::path::append(Dir, Name);
2127     if (llvm::sys::fs::can_execute(Twine(Dir)))
2128       return true;
2129     llvm::sys::path::remove_filename(Dir);
2130   }
2131   return false;
2132 }
2133 
2134 std::string Driver::GetProgramPath(const char *Name,
2135                                    const ToolChain &TC) const {
2136   SmallVector<std::string, 2> TargetSpecificExecutables;
2137   generatePrefixedToolNames(Name, TC, TargetSpecificExecutables);
2138 
2139   // Respect a limited subset of the '-Bprefix' functionality in GCC by
2140   // attempting to use this prefix when looking for program paths.
2141   for (const auto &PrefixDir : PrefixDirs) {
2142     if (llvm::sys::fs::is_directory(PrefixDir)) {
2143       SmallString<128> P(PrefixDir);
2144       if (ScanDirForExecutable(P, TargetSpecificExecutables))
2145         return P.str();
2146     } else {
2147       SmallString<128> P(PrefixDir + Name);
2148       if (llvm::sys::fs::can_execute(Twine(P)))
2149         return P.str();
2150     }
2151   }
2152 
2153   const ToolChain::path_list &List = TC.getProgramPaths();
2154   for (const auto &Path : List) {
2155     SmallString<128> P(Path);
2156     if (ScanDirForExecutable(P, TargetSpecificExecutables))
2157       return P.str();
2158   }
2159 
2160   // If all else failed, search the path.
2161   for (const auto &TargetSpecificExecutable : TargetSpecificExecutables)
2162     if (llvm::ErrorOr<std::string> P =
2163             llvm::sys::findProgramByName(TargetSpecificExecutable))
2164       return *P;
2165 
2166   return Name;
2167 }
2168 
2169 std::string Driver::GetTemporaryPath(StringRef Prefix,
2170                                      const char *Suffix) const {
2171   SmallString<128> Path;
2172   std::error_code EC = llvm::sys::fs::createTemporaryFile(Prefix, Suffix, Path);
2173   if (EC) {
2174     Diag(clang::diag::err_unable_to_make_temp) << EC.message();
2175     return "";
2176   }
2177 
2178   return Path.str();
2179 }
2180 
2181 const ToolChain &Driver::getToolChain(const ArgList &Args,
2182                                       const llvm::Triple &Target) const {
2183 
2184   ToolChain *&TC = ToolChains[Target.str()];
2185   if (!TC) {
2186     switch (Target.getOS()) {
2187     case llvm::Triple::CloudABI:
2188       TC = new toolchains::CloudABI(*this, Target, Args);
2189       break;
2190     case llvm::Triple::Darwin:
2191     case llvm::Triple::MacOSX:
2192     case llvm::Triple::IOS:
2193       TC = new toolchains::DarwinClang(*this, Target, Args);
2194       break;
2195     case llvm::Triple::DragonFly:
2196       TC = new toolchains::DragonFly(*this, Target, Args);
2197       break;
2198     case llvm::Triple::OpenBSD:
2199       TC = new toolchains::OpenBSD(*this, Target, Args);
2200       break;
2201     case llvm::Triple::Bitrig:
2202       TC = new toolchains::Bitrig(*this, Target, Args);
2203       break;
2204     case llvm::Triple::NetBSD:
2205       TC = new toolchains::NetBSD(*this, Target, Args);
2206       break;
2207     case llvm::Triple::FreeBSD:
2208       TC = new toolchains::FreeBSD(*this, Target, Args);
2209       break;
2210     case llvm::Triple::Minix:
2211       TC = new toolchains::Minix(*this, Target, Args);
2212       break;
2213     case llvm::Triple::Linux:
2214       if (Target.getArch() == llvm::Triple::hexagon)
2215         TC = new toolchains::HexagonToolChain(*this, Target, Args);
2216       else
2217         TC = new toolchains::Linux(*this, Target, Args);
2218       break;
2219     case llvm::Triple::NaCl:
2220       TC = new toolchains::NaClToolChain(*this, Target, Args);
2221       break;
2222     case llvm::Triple::Solaris:
2223       TC = new toolchains::Solaris(*this, Target, Args);
2224       break;
2225     case llvm::Triple::AMDHSA:
2226       TC = new toolchains::AMDGPUToolChain(*this, Target, Args);
2227       break;
2228     case llvm::Triple::Win32:
2229       switch (Target.getEnvironment()) {
2230       default:
2231         if (Target.isOSBinFormatELF())
2232           TC = new toolchains::Generic_ELF(*this, Target, Args);
2233         else if (Target.isOSBinFormatMachO())
2234           TC = new toolchains::MachO(*this, Target, Args);
2235         else
2236           TC = new toolchains::Generic_GCC(*this, Target, Args);
2237         break;
2238       case llvm::Triple::GNU:
2239         TC = new toolchains::MinGW(*this, Target, Args);
2240         break;
2241       case llvm::Triple::Itanium:
2242         TC = new toolchains::CrossWindowsToolChain(*this, Target, Args);
2243         break;
2244       case llvm::Triple::MSVC:
2245       case llvm::Triple::UnknownEnvironment:
2246         TC = new toolchains::MSVCToolChain(*this, Target, Args);
2247         break;
2248       }
2249       break;
2250     case llvm::Triple::CUDA:
2251       TC = new toolchains::CudaToolChain(*this, Target, Args);
2252       break;
2253     default:
2254       // Of these targets, Hexagon is the only one that might have
2255       // an OS of Linux, in which case it got handled above already.
2256       switch (Target.getArch()) {
2257       case llvm::Triple::tce:
2258         TC = new toolchains::TCEToolChain(*this, Target, Args);
2259         break;
2260       case llvm::Triple::hexagon:
2261         TC = new toolchains::HexagonToolChain(*this, Target, Args);
2262         break;
2263       case llvm::Triple::xcore:
2264         TC = new toolchains::XCoreToolChain(*this, Target, Args);
2265         break;
2266       case llvm::Triple::wasm32:
2267       case llvm::Triple::wasm64:
2268         TC = new toolchains::WebAssembly(*this, Target, Args);
2269         break;
2270       default:
2271         if (Target.getVendor() == llvm::Triple::Myriad)
2272           TC = new toolchains::MyriadToolChain(*this, Target, Args);
2273         else if (Target.isOSBinFormatELF())
2274           TC = new toolchains::Generic_ELF(*this, Target, Args);
2275         else if (Target.isOSBinFormatMachO())
2276           TC = new toolchains::MachO(*this, Target, Args);
2277         else
2278           TC = new toolchains::Generic_GCC(*this, Target, Args);
2279       }
2280     }
2281   }
2282   return *TC;
2283 }
2284 
2285 bool Driver::ShouldUseClangCompiler(const JobAction &JA) const {
2286   // Say "no" if there is not exactly one input of a type clang understands.
2287   if (JA.size() != 1 || !types::isAcceptedByClang((*JA.begin())->getType()))
2288     return false;
2289 
2290   // And say "no" if this is not a kind of action clang understands.
2291   if (!isa<PreprocessJobAction>(JA) && !isa<PrecompileJobAction>(JA) &&
2292       !isa<CompileJobAction>(JA) && !isa<BackendJobAction>(JA))
2293     return false;
2294 
2295   return true;
2296 }
2297 
2298 /// GetReleaseVersion - Parse (([0-9]+)(.([0-9]+)(.([0-9]+)?))?)? and return the
2299 /// grouped values as integers. Numbers which are not provided are set to 0.
2300 ///
2301 /// \return True if the entire string was parsed (9.2), or all groups were
2302 /// parsed (10.3.5extrastuff).
2303 bool Driver::GetReleaseVersion(const char *Str, unsigned &Major,
2304                                unsigned &Minor, unsigned &Micro,
2305                                bool &HadExtra) {
2306   HadExtra = false;
2307 
2308   Major = Minor = Micro = 0;
2309   if (*Str == '\0')
2310     return false;
2311 
2312   char *End;
2313   Major = (unsigned)strtol(Str, &End, 10);
2314   if (*Str != '\0' && *End == '\0')
2315     return true;
2316   if (*End != '.')
2317     return false;
2318 
2319   Str = End + 1;
2320   Minor = (unsigned)strtol(Str, &End, 10);
2321   if (*Str != '\0' && *End == '\0')
2322     return true;
2323   if (*End != '.')
2324     return false;
2325 
2326   Str = End + 1;
2327   Micro = (unsigned)strtol(Str, &End, 10);
2328   if (*Str != '\0' && *End == '\0')
2329     return true;
2330   if (Str == End)
2331     return false;
2332   HadExtra = true;
2333   return true;
2334 }
2335 
2336 std::pair<unsigned, unsigned> Driver::getIncludeExcludeOptionFlagMasks() const {
2337   unsigned IncludedFlagsBitmask = 0;
2338   unsigned ExcludedFlagsBitmask = options::NoDriverOption;
2339 
2340   if (Mode == CLMode) {
2341     // Include CL and Core options.
2342     IncludedFlagsBitmask |= options::CLOption;
2343     IncludedFlagsBitmask |= options::CoreOption;
2344   } else {
2345     ExcludedFlagsBitmask |= options::CLOption;
2346   }
2347 
2348   return std::make_pair(IncludedFlagsBitmask, ExcludedFlagsBitmask);
2349 }
2350 
2351 bool clang::driver::isOptimizationLevelFast(const ArgList &Args) {
2352   return Args.hasFlag(options::OPT_Ofast, options::OPT_O_Group, false);
2353 }
2354